Convert hours and minutes to decimal hours and back, with quarter-hour and tenth-hour rounding built in.
Type a time as HH:MM or as separate boxes. The decimal figure is what payroll, invoicing and spreadsheet software expects.
Decimal hours
7.75
7 hours and 45 minutes
Enter a decimal figure such as 7.75 or 6.4 and get the equivalent clock-style duration.
Hours and minutes
7:45
7 hours and 45 minutes
To convert time to decimal hours, divide the minutes by 60 and add the result to the hours, so 7 hours 30 minutes is 7.5 decimal hours, never 7.30. The clock counts minutes to 60, but a decimal number counts to 100, so the two notations only agree at the quarter marks. Writing a shift of 7:30 as 7.30 on a timesheet quietly deletes 12 minutes of paid work. To go back the other way, multiply the fractional part by 60: 7.75 hours is 0.75 × 60 = 45 minutes, so 7:45.
decimal hours = hours + (minutes ÷ 60) + (seconds ÷ 3600) 7:30 → 7 + (30 ÷ 60) = 7.500 7:45 → 7 + (45 ÷ 60) = 7.750 7:20 → 7 + (20 ÷ 60) = 7.333A decimal hours converter changes a time written in hours and minutes into a single number with a fractional part, and changes it back again. That sounds trivial, and it is the single most error-prone conversion in payroll and invoicing. The reason is that both notations use a full stop or a colon in the same visual position, so 7:30 and 7.30 look almost identical on a printed timesheet while differing by 12 minutes of pay.
The tool at the top of this page works in both directions:
7:45 straight into the free-text field. You get the exact decimal to three places, a two-decimal figure for payroll entry, the value rounded to the nearest quarter hour, the value rounded to the nearest tenth of an hour, the tidy HH:MM:SS form, and the total in minutes.6.35 and you get 6:21, 6:21:00, the whole-hour part, the minutes part on its own, and the totals in minutes and seconds. This is the direction people need when an invoice, a project tracker or a payroll export hands them a decimal and the schedule needs a clock reading.Everything runs locally in your browser. Nothing is uploaded, nothing is stored, and once the page is loaded it keeps working with the connection off. If you need to add several time values together before converting them, do the addition on the Time Calculator first, then bring the total here. If you are starting from a raw minute count rather than a clock reading, the Minutes to Hours converter is the shorter path.
The rest of this page is the reference material that goes with the tool: a complete chart of every minute from 1 to 60, the quarter-hour and tenth-hour billing increments used by law firms and agencies, the spreadsheet formulas for Excel and Google Sheets, and a straight accounting of what the conversion costs when it goes wrong.
Four steps, about fifteen seconds. Both tabs update as you type, and every output is selectable so you can copy the exact figure your system wants.
Use Time to Decimal when you have a clock reading such as 7 h 45 min and need a payroll number. Use Decimal to Time when you have a number such as 7.75 and need a schedule reading.
Fill the hours, minutes and seconds boxes, or paste a whole value such as 7:45 or 7:45:30 into the free-text field. Blank boxes count as zero, and minute values above 59 are normalised for you.
Read the exact figure to three decimal places, take the two-decimal version most payroll systems accept, or press round to nearest quarter hour if that is your employer's stated policy.
Decimal hours go into payroll and invoices. HH:MM:SS goes into rosters and schedules. Total minutes goes into billing systems that count in minutes rather than hours.
Convert last, not first. If you are totalling a week of shifts, add the HH:MM values together first and convert the single total once. Converting each day and then adding the rounded decimals is how a week ends up one or two minutes short. The Time Card Calculator does the weekly addition and hands you one number to convert.
One notation counts to 60, the other counts to 100. Confusing them always costs the worker and never the payer.
A clock reading of 7:30 means seven whole hours plus thirty sixtieths of another hour. Thirty sixtieths is one half, so the decimal value is 7.5. The number 7.30, read as an ordinary decimal, means seven whole hours plus thirty hundredths of another hour. Thirty hundredths of 60 minutes is 18 minutes. So the two readings are 7 h 30 min and 7 h 18 min, and the gap between them is twelve minutes of work that nobody gets paid for.
minutes lost = M − (M × 0.6) = M × 0.4 where M is the minutes part of the clock reading M = 30 → 30 × 0.4 = 12 minutes lost M = 45 → 45 × 0.4 = 18 minutes lost M = 55 → 55 × 0.4 = 22 minutes lost
That formula is worth committing to memory, because it makes the size of the mistake predictable. The error is always four tenths of the minutes part, expressed in minutes. It is zero on the hour, it grows steadily through the hour, and it peaks at 23.6 minutes when the clock reads 59 minutes past. It is also always in the same direction, because a hundredth of an hour is smaller than a sixtieth of an hour. Written as HH.MM, a shift is never overstated. It is understated every single time.
| Time worked | Written as | True decimal | Minutes lost per shift | Lost per 5-day week | Weekly cost |
|---|---|---|---|---|---|
| 7:05 | 7.05 | 7.083 | 2 min | 10 min | $4.75 |
| 7:15 | 7.15 | 7.250 | 6 min | 30 min | $14.25 |
| 7:30 | 7.30 | 7.500 | 12 min | 60 min | $28.50 |
| 7:45 | 7.45 | 7.750 | 18 min | 90 min | $42.75 |
| 8:20 | 8.20 | 8.333 | 8 min | 40 min | $19.00 |
| 8:40 | 8.40 | 8.667 | 16 min | 80 min | $38.00 |
| 8:50 | 8.50 | 8.833 | 20 min | 100 min | $47.50 |
| 9:55 | 9.55 | 9.917 | 22 min | 110 min | $52.25 |
The rate of $28.50 an hour is used throughout this page as a worked figure so the arithmetic can be checked. Substitute your own rate: the minutes lost stay the same, only the money changes. A worker on 7:30 shifts loses one hour of pay every week, which is 52 hours and $1,482.00 across a full year.
Gross pay is a multiplication: hours × rate. You cannot multiply 7:45 by $28.50 in any spreadsheet or payroll engine, but 7.75 × 28.50 = $220.88 works everywhere. Decimal hours are what make a duration compatible with money.
Because hundredths are smaller than sixtieths, HH.MM always understates. Nobody ever accidentally overpays with this error, which is why an auditor treats a timesheet column full of values like 7.15, 7.30 and 7.45 as a red flag.
A true decimal hours column can contain 7.75 and 7.33. It can never contain a value with a minutes-style number after the point, because .60 through .99 are legal decimals but 60 through 99 are not legal minutes. Scan a column for values ending .60 or higher: those are unambiguous.
The mistake runs in reverse too. Reading a decimal as if it were a clock value is just as common and can go either way. Someone told a task took 7.75 hours who writes it down as 7 hours 75 minutes has recorded 8:15 instead of 7:45, overstating by half an hour. Someone who reads 7.5 as 7 hours 5 minutes has understated by 25 minutes. Always multiply the fraction by 60.
Two formulas, one in each direction, and one repeating decimal that explains why three places is the practical floor.
Each unit is divided by the number of that unit in one hour. Minutes are sixtieths of an hour, seconds are three-thousand-six-hundredths of an hour, and the hours part passes through untouched.
decimal = hours + (minutes ÷ 60) + (seconds ÷ 3600) 6:42:00 → 6 + 0.700 + 0 = 6.700 6:42:30 → 6 + 0.700 + 0.00833 = 6.708
An equivalent method that some people find easier: convert the whole thing to minutes first, then divide the single total by 60. For 6:42 that is (6 × 60) + 42 = 402 minutes, and 402 ÷ 60 = 6.7. The two routes always agree, and the second one is less prone to slips when seconds are involved, because you can convert the seconds with the Seconds to Minutes converter first and then work in one unit.
Split the number at the decimal point. The whole part is the hours. The fractional part multiplied by 60 gives the minutes, and any remaining fraction of a minute multiplied by 60 again gives the seconds.
hours = floor(decimal) minutes = floor((decimal − hours) × 60) seconds = round((((decimal − hours) × 60) − minutes) × 60) 6.708 → hours 6, 0.708 × 60 = 42.48 min → 42 min, 0.48 × 60 = 29 s → 6:42:29
The hour was divided into sixty parts because the sexagesimal counting system inherited from Babylonian astronomy divides cleanly by 2, 3, 4, 5, 6, 10, 12, 15, 20 and 30. That is a genuinely useful property: a third of an hour is a whole number of minutes, and so is a fifth and a twelfth. Decimal notation cannot do this. A third of an hour in decimal is 0.333333 forever.
This is the reason a decimal hours column is never perfectly exact. One minute is 1 ÷ 60 = 0.0166666 recurring. Rounded to three places it becomes 0.017, which is 61.2 seconds rather than 60, an overstatement of 1.2 seconds. Rounded to two places it becomes 0.02, which is 72 seconds, an overstatement of a fifth of a minute. Three places keeps every single-minute value within about a second of the truth, which is why the chart below is given to three places and why the converter reports three.
The only minute values that land on an exact short decimal are the ones where the minutes divide 60 evenly into a terminating fraction: 6, 12, 15, 18, 24, 30, 36, 42, 45, 48, 54 and 60. Every other minute recurs. That is not a flaw in the arithmetic, it is what happens when a base-60 quantity is written in base 10.
1 minute = 0.016666... → 0.017 at 3 dp 5 minutes = 0.083333... → 0.083 at 3 dp 20 minutes = 0.333333... → 0.333 at 3 dp 40 minutes = 0.666666... → 0.667 at 3 dp
The complete conversion table, to three decimal places. Print it, pin it above the desk, or check a single value against it before you type a timesheet.
| Min | Decimal | Min | Decimal | Min | Decimal | Min | Decimal |
|---|---|---|---|---|---|---|---|
| 1 | 0.017 | 16 | 0.267 | 31 | 0.517 | 46 | 0.767 |
| 2 | 0.033 | 17 | 0.283 | 32 | 0.533 | 47 | 0.783 |
| 3 | 0.050 | 18 | 0.300 | 33 | 0.550 | 48 | 0.800 |
| 4 | 0.067 | 19 | 0.317 | 34 | 0.567 | 49 | 0.817 |
| 5 | 0.083 | 20 | 0.333 | 35 | 0.583 | 50 | 0.833 |
| 6 | 0.100 | 21 | 0.350 | 36 | 0.600 | 51 | 0.850 |
| 7 | 0.117 | 22 | 0.367 | 37 | 0.617 | 52 | 0.867 |
| 8 | 0.133 | 23 | 0.383 | 38 | 0.633 | 53 | 0.883 |
| 9 | 0.150 | 24 | 0.400 | 39 | 0.650 | 54 | 0.900 |
| 10 | 0.167 | 25 | 0.417 | 40 | 0.667 | 55 | 0.917 |
| 11 | 0.183 | 26 | 0.433 | 41 | 0.683 | 56 | 0.933 |
| 12 | 0.200 | 27 | 0.450 | 42 | 0.700 | 57 | 0.950 |
| 13 | 0.217 | 28 | 0.467 | 43 | 0.717 | 58 | 0.967 |
| 14 | 0.233 | 29 | 0.483 | 44 | 0.733 | 59 | 0.983 |
| 15 | 0.250 | 30 | 0.500 | 45 | 0.750 | 60 | 1.000 |
Read down each pair of columns: minutes 1 to 15, then 16 to 30, then 31 to 45, then 46 to 60. The bold final row holds the four quarter-hour marks, the only values where the clock reading and a two-place decimal look anything like each other. To use the chart, take the minutes part of your time, find its decimal, and add it to the whole hours. For 9 h 23 min, look up 23 to get 0.383 and the answer is 9.383.
| Shift | HH:MM | Total minutes | Decimal hours | Pay at $28.50 |
|---|---|---|---|---|
| Half day | 4:00 | 240 | 4.000 | $114.00 |
| Short shift | 5:30 | 330 | 5.500 | $156.75 |
| Six hour shift | 6:00 | 360 | 6.000 | $171.00 |
| Seven and a quarter | 7:15 | 435 | 7.250 | $206.63 |
| Eight hours less 30 min lunch | 7:30 | 450 | 7.500 | $213.75 |
| Eight hours less 15 min break | 7:45 | 465 | 7.750 | $220.88 |
| Standard shift | 8:00 | 480 | 8.000 | $228.00 |
| Shift plus 20 min handover | 8:20 | 500 | 8.333 | $237.50 |
| Shift plus 30 min | 8:30 | 510 | 8.500 | $242.25 |
| Nine hour shift | 9:00 | 540 | 9.000 | $256.50 |
| Ten hour shift | 10:00 | 600 | 10.000 | $285.00 |
| Twelve hour shift | 12:00 | 720 | 12.000 | $342.00 |
| Twelve and a half | 12:30 | 750 | 12.500 | $356.25 |
| Part-time week | 22:30 | 1,350 | 22.500 | $641.25 |
| Reduced full-time week | 37:30 | 2,250 | 37.500 | $1,068.75 |
| Standard full-time week | 40:00 | 2,400 | 40.000 | $1,140.00 |
Pay figures are gross, before deductions, and are rounded to the cent. Note the 7:15 row: 7.25 × 28.50 is $206.625, which rounds to $206.63. Payroll systems differ on whether they round the hours, the pay, or both, so a cent of disagreement between your figure and the pay slip is usually a rounding rule and not an error. For a whole week of clock-in and clock-out pairs, build the total on the Time Card Calculator and convert the single result here.
Multiply the part after the point by 60. That is the whole rule, and it is the step most people skip.
The reverse conversion matters more often than people expect. Project trackers, time-tracking apps and payroll exports nearly all report in decimal, but rosters, schedules and conversations happen in hours and minutes. When a report says a task took 3.4 hours, nobody knows what that means until it is turned back into 3 h 24 min.
minutes = (decimal − whole hours) × 60 3.40 → 0.40 × 60 = 24 min → 3:24 6.85 → 0.85 × 60 = 51 min → 6:51 8.75 → 0.75 × 60 = 45 min → 8:45 5.08 → 0.08 × 60 = 4.8 min → 5:04:48
Two things are worth noticing in that block. First, a decimal that is a multiple of 0.05 always lands on a whole number of minutes, because 0.05 of an hour is exactly 3 minutes. Second, anything else lands part way through a minute, which is why the last line carries seconds. If your output has to be whole minutes, round at that point and accept a difference of up to 30 seconds.
| Decimal | Minutes | Decimal | Minutes | Decimal | Minutes | Decimal | Minutes |
|---|---|---|---|---|---|---|---|
| 0.05 | 3 min | 0.30 | 18 min | 0.55 | 33 min | 0.80 | 48 min |
| 0.10 | 6 min | 0.35 | 21 min | 0.60 | 36 min | 0.85 | 51 min |
| 0.15 | 9 min | 0.40 | 24 min | 0.65 | 39 min | 0.90 | 54 min |
| 0.20 | 12 min | 0.45 | 27 min | 0.70 | 42 min | 0.95 | 57 min |
| 0.25 | 15 min | 0.50 | 30 min | 0.75 | 45 min | 1.00 | 60 min |
Values between these steps do not land on a whole minute. The two you will meet most are 0.33, which is 19 min 48 s rather than 20 minutes, and 0.67, which is 40 min 12 s rather than 40 minutes. If a report shows 0.33 and you need exactly 20 minutes, the underlying value was 0.3333 and someone truncated it. For converting a long list of decimals back into readable spans, the Time Duration Calculator handles the durations and this page handles the notation.
Watch the roll-over at the top of the hour. A decimal of 7.999 gives 0.999 × 60 = 59.94 minutes. Rounded to the nearest minute that is 60, which is not a legal minutes value, so the result has to roll to 8:00. The converter handles this, but a hand-built spreadsheet formula usually does not, and it will happily display 7:60.
Rounding is a policy decision, not an arithmetic one. Decide the increment, decide the direction, apply it once, and write it down.
Two rounding grids dominate paid work. Payroll runs on the quarter hour, a fifteen-minute increment giving the familiar 0.25, 0.50, 0.75 and 1.00. Professional services run on the tenth of an hour, a six-minute increment giving 0.1 through 1.0. Law firms, accountants, consultancies and many creative agencies bill in tenths because six minutes is short enough to feel fair to the client and long enough to keep a timesheet from becoming a stopwatch log.
Within each grid there are two directions. Nearest rounding moves a value to whichever mark is closer, so it sometimes gains and sometimes loses, and over many entries it comes out roughly even. Round up always moves to the next mark, so it always gains for whoever is billing. Round up is normal in professional billing, where any contact with a matter starts a new unit, and it is not normal in payroll, where systematically rounding a worker's time in the employer's favour is the thing regulators object to.
| Grid | Increment | Minutes | Nearest band | Round-up band |
|---|---|---|---|---|
| Quarter hour | 0.00 | 0 | 0 to 7 | 0 only |
| Quarter hour | 0.25 | 15 | 8 to 22 | 1 to 15 |
| Quarter hour | 0.50 | 30 | 23 to 37 | 16 to 30 |
| Quarter hour | 0.75 | 45 | 38 to 52 | 31 to 45 |
| Quarter hour | 1.00 | 60 | 53 to 60 | 46 to 60 |
| Tenth hour | 0.1 | 6 | 3 to 8 | 1 to 6 |
| Tenth hour | 0.2 | 12 | 9 to 14 | 7 to 12 |
| Tenth hour | 0.3 | 18 | 15 to 20 | 13 to 18 |
| Tenth hour | 0.4 | 24 | 21 to 26 | 19 to 24 |
| Tenth hour | 0.5 | 30 | 27 to 32 | 25 to 30 |
| Tenth hour | 0.6 | 36 | 33 to 38 | 31 to 36 |
| Tenth hour | 0.7 | 42 | 39 to 44 | 37 to 42 |
| Tenth hour | 0.8 | 48 | 45 to 50 | 43 to 48 |
| Tenth hour | 0.9 | 54 | 51 to 56 | 49 to 54 |
| Tenth hour | 1.0 | 60 | 57 to 60 | 55 to 60 |
The quarter-hour nearest bands are what North American payroll practice calls the seven-minute rule: 1 to 7 minutes past the mark rounds back, 8 to 14 rounds forward. In the United States the Fair Labor Standards Act permits rounding of clock punches only where the practice is neutral over time and does not consistently work against the employee, so a policy that only ever rounds down is the one that gets challenged. Canadian provincial employment standards generally require that all time worked is paid, so rounding there is a payroll convenience that must not reduce total pay.
The second half of rounding policy is precision, and it causes quieter errors than the quarter-hour question. Every time you round, you throw away a small amount. Round once and the loss is negligible. Round every row of a timesheet and the losses add up in the same direction, because the values that recur, such as 20 and 40 minutes, always round the same way.
five days of 7:20 true total = 5 × 7.33333 = 36.66667 h = 36 h 40 min rounded daily = 5 × 7.33 = 36.65 h = 36 h 39 min difference = 0.01667 h = 1 minute
One minute a week is small, but the same mechanism scales. A field service business logging 20-minute call-outs at two decimal places loses 12 seconds on every entry, because 0.333333 becomes 0.33. A hundred call-outs is 1,200 seconds, which is exactly 20 minutes, or one entire unbilled call-out. At three decimal places the same hundred entries lose 20 seconds in total. The rule that follows is simple: keep three decimal places through every intermediate step, and round only the number that leaves the building.
Better still, do the intermediate arithmetic in minutes, where nothing recurs and nothing is lost, and convert to decimal exactly once at the end. Adding 440 + 465 + 415 + 490 + 500 minutes is exact integer arithmetic. The single division by 60 at the end is the only place a rounding decision has to be made. This is how the Hours Calculator totals a week, and it is why its total will occasionally differ by a minute from a spreadsheet that rounded as it went.
The first shows where the two scales agree and where they do not. The second shows what a week of the wrong notation costs.
Both applications store a time as a fraction of a day. That one fact explains every formula below, including the ones that look strange.
When you type 7:45 into a cell, neither Excel nor Google Sheets stores the text "7:45". It stores the number 0.322917, which is 7.75 divided by 24, because internally a whole day is 1.0 and a time is the fraction of the day that has passed. The cell only looks like a clock because of its number format.
Once you know that, the master formula falls out immediately. To turn a stored time into decimal hours, multiply by 24. To turn decimal hours back into a stored time, divide by 24.
decimal hours = time cell × 24 → 0.322917 × 24 = 7.75 stored time = decimal ÷ 24 → 7.75 ÷ 24 = 0.322917 total minutes = time cell × 1440 total seconds = time cell × 86400
| What you want | Excel | Google Sheets | Format the result as |
|---|---|---|---|
| Time to decimal hours | =A2*24 | =A2*24 | Number, 2 or 3 decimal places |
| Hours and minutes in two columns | =B2+C2/60 | =B2+C2/60 | Number, 2 or 3 decimal places |
| Text such as "7:45" to decimal | =TIMEVALUE(A2)*24 | =TIMEVALUE(A2)*24 | Number |
| Decimal hours back to a time | =A2/24 | =A2/24 | Custom [h]:mm or Duration |
| Decimal hours as HH:MM text | =TEXT(A2/24,"[h]:mm") | =TEXT(A2/24,"[h]:mm") | Text, no format needed |
| Total a week of HH:MM | =SUM(A2:A8) | =SUM(A2:A8) | Custom [h]:mm, never h:mm |
| Total a week as one decimal | =SUM(A2:A8)*24 | =SUM(A2:A8)*24 | Number, 2 decimal places |
| Total minutes | =A2*1440 | =A2*1440 | Number, 0 decimal places |
| Round to nearest quarter hour | =MROUND(A2*24,0.25) | =MROUND(A2*24,0.25) | Number, 2 decimal places |
| Round up to the next tenth | =CEILING(A2*24,0.1) | =CEILING(A2*24,0.1) | Number, 1 decimal place |
| Round down to the last tenth | =FLOOR(A2*24,0.1) | =FLOOR(A2*24,0.1) | Number, 1 decimal place |
| Gross pay from a time value | =ROUND(A2*24*$B$1,2) | =ROUND(A2*24*$B$1,2) | Currency, with the rate in B1 |
| Shift length from two punches | =(C2−B2)*24 | =(C2−B2)*24 | Number, 2 decimal places |
| Shift that crosses midnight | =MOD(C2−B2,1)*24 | =MOD(C2−B2,1)*24 | Number, 2 decimal places |
The MOD trick on the last row is the standard fix for an overnight shift: subtracting a 22:00 start from a 06:00 end gives a negative fraction, and taking it modulo 1 wraps it back into the correct 8 hours. If you would rather not maintain the formula, the Time Duration Calculator detects the midnight crossing automatically.
Two formatting traps eat entire days of work. First, a total of 40 hours displayed with the format h:mm shows as 16:00, because the format wraps at 24 just like a clock. Use [h]:mm with the square brackets and it shows 40:00. Second, when you multiply a time by 24 the new cell often inherits the time format from the cell it came from, so 7.75 renders as 18:00 (three quarters of a day). The number is right, the format is wrong. Set the result cell to Number.
One more habit worth building: put the conversion in its own column rather than burying *24 inside a longer formula. A column of visible decimal hours can be eyeballed against the chart on this page, and anyone who inherits the file can see where the conversion happened. A hidden *24 inside a pay calculation is invisible until the year end, and by then it has been wrong for eleven months.
Each of these is solvable in the converter above. The steps are shown so you can check your own method line by line.
Clock in 06:52, clock out 15:19, with a 30-minute unpaid break. The payroll portal accepts decimal hours only.
= 7:57:00 → 7.95 decimal hours
Five paid shifts: 7:45, 8:10, 6:55, 8:30 and 7:20. The rate is $31.00 an hour.
= 38:40:00 → 38.667 decimal hours
Four pieces of work on one matter: 12 min, 25 min, 7 min and 48 min. The firm bills in tenths, rounded up, at $340 an hour.
= 1.7 billable hours, $578.00
A supplier invoice lists 12.60 hours of on-site work and you need to know what to write in the site log.
= 12:36:00
A support desk logs 20-minute call-outs and records each one at two decimal places. There were 100 of them.
Fix: store 0.333 and lose only 20 seconds in total
A week totals 43 h 20 min. Anything over 40 hours pays at time and a half on a base of $28.50.
= $1,282.50 gross for 43:20
Anywhere a duration is multiplied by money, the duration has to become a decimal first.
Nearly every payroll engine takes hours as a decimal and refuses HH:MM outright. Punches are totalled, breaks removed, the result converted, and the decimal keyed or imported.
An invoice line reads "6.75 hours at $95". Getting there means totalling tracked entries in HH:MM and converting exactly once, at the end, before the multiplication.
The billable hour is divided into ten units of six minutes. Every entry is a tenth, and a matter summary is a column of tenths that has to add up to something a client will accept.
Rotating rosters produce shifts like 11 h 38 min after handover. Converting to 11.633 is what turns an awkward roster into a payable number.
Reconciling a supplier invoice against a site log means converting in both directions, because the invoice speaks decimal and the log speaks clock time.
Crew hours, plant hire and call-outs are all quoted per hour. Field notes arrive as clock times and have to leave as decimals on a job costing sheet.
Absence balances, time off in lieu and contracted hours are all held as decimals, so a request for "half a day" has to become 3.75 or 4.00 depending on the contract.
Decimal time conversion is a standard fraction exercise: 45 minutes as a fraction of an hour is three quarters, and three quarters as a decimal is 0.75. Same skill, real money attached.
Rosters are published in 24-hour clock time and paid in decimals. If the roster format is the sticking point rather than the arithmetic, start at the Military Time Converter.
There are four realistic ways to get from 7:47 to 7.783. They differ mostly in how they fail.
| Method | Accuracy | Reverse direction | Quarter and tenth rounding | How it fails |
|---|---|---|---|---|
| Mental arithmetic | Good on the quarters, weak elsewhere | Rarely attempted | By eye | Defaults to the HH.MM trap under time pressure |
| Pocket calculator | Exact if you remember to divide by 60 | Yes, multiply by 60 | Manual | Nothing stops you typing 7.30 and moving on |
| Printed chart | Exact at the printed increments | Needs a second chart | Only if printed | Silently out of date, and no seconds |
| Spreadsheet formula | Exact, full precision held internally | Yes, divide by 24 | MROUND and CEILING | Cell formatting, and totals wrapping at 24 hours |
| This converter recommended | Exact to 3 places, seconds included | Yes, dedicated tab | Both, one press | Needs the page open once, then works offline |
The printed chart still earns its place on a wall next to a punch clock, which is why the full 1 to 60 chart above is laid out to print cleanly. The spreadsheet is the right answer for a recurring monthly process. The converter is the right answer for the value in front of you right now.
Every wrong decimal hours figure traces back to one of these seven, and five of them are invisible on the page.
| Mistake | What it looks like | The fix |
|---|---|---|
| Copying the minutes after the point | 7:30 entered as 7.30 | Divide the minutes by 60. 7:30 is 7.50, and the gap is 12 minutes per shift. |
| Reading a decimal as minutes | 7.75 read as 7 h 75 min | Multiply the fraction by 60. 7.75 is 7:45, and reading it as 75 minutes overstates by 30 minutes. |
| Rounding every row, then summing | 5 × 7.33 = 36.65 | Keep three places to the end. The true total is 36.667, or 36 h 40 min. |
| Dropping the seconds | 7:45:30 entered as 7.75 | Seconds are thirty-six-hundredths of a minute. 7:45:30 is 7.758. |
| Formatting a total as h:mm | A 40:00 week shows 16:00 | Use [h]:mm with square brackets, otherwise the total wraps at 24 hours. |
| Rounding always in one direction | Every punch rounded down | Use nearest, not always down, unless the policy is written and lawful in your jurisdiction. |
| Mixing formats in one column | 7.5 and 7:30 side by side | Convert everything to one notation before adding. A column of mixed formats cannot be summed at all. |
The fastest audit for a suspect timesheet: scan the decimal column for any value whose digits after the point are between .60 and .99 and look like a plausible minute count, such as .75 next to .45 and .30 in the same column. A genuine decimal column contains .75; a corrupted one contains .45 where .75 should be. If you are auditing several weeks, rebuild the totals in the Hours Calculator from the raw punches rather than trusting the converted column.
The vocabulary you will meet on timesheets, invoices and payroll exports.
Direct answers to the questions people ask most about this calculation.
A decimal hours converter turns a time written in hours and minutes into a single number with a fractional part, and turns that number back into hours and minutes. It exists because payroll systems, invoices and spreadsheets multiply hours by a rate, and you cannot multiply 7:45 by an hourly rate. Converted to 7.75, the multiplication works anywhere.
Divide the minutes by 60. For example 45 minutes divided by 60 is 0.75, so 7 hours 45 minutes is 7.75 decimal hours. For 20 minutes the answer is 0.333, and for 50 minutes it is 0.833. The full chart on this page lists every minute from 1 to 60 to three decimal places, so you can look up a value rather than dividing.
7:30 is 7.5 decimal hours. Thirty minutes is half an hour, and half of 1.00 is 0.50, not 0.30. Writing 7.30 records seven hours and eighteen minutes, understating the shift by twelve minutes. Repeated across a five-day week that is one full hour of unpaid work, and across a year it is roughly 52 hours.
Keep the whole number as the hours, then multiply the part after the decimal point by 60 to get the minutes. For 6.85 hours, 0.85 multiplied by 60 is 51, so the answer is 6 hours 51 minutes. If the result is not a whole number of minutes, multiply the leftover fraction by 60 again to get the seconds.
45 minutes is 0.75 decimal hours, because 45 divided by 60 is three quarters. The other quarter marks are 15 minutes as 0.25, 30 minutes as 0.50 and 60 minutes as 1.00. These four are the only values where the clock reading and the decimal look at all similar, which is part of why the other 56 values cause so much trouble.
Because gross pay is a multiplication and HH:MM cannot be multiplied. The colon is a separator, not a decimal point, so 7:45 has no numeric value a payroll engine can use. Converted to 7.75, the calculation 7.75 multiplied by an hourly rate of $28.50 gives $220.88 directly. Every mainstream payroll system therefore takes hours as a decimal.
Multiply the cell by 24, then format the result as a Number rather than a time. Both applications store a time as a fraction of a day, so 7:45 is held as 0.322917, and 0.322917 multiplied by 24 is 7.75. To reverse it, divide the decimal by 24 and format the cell as [h]:mm. The square brackets stop totals wrapping at 24 hours.
0.1 of an hour is 6 minutes, because one tenth of 60 is 6. This is the billing unit used by law firms, accountants and many consultancies, where every entry on a matter is recorded as a whole number of tenths. So 0.3 is 18 minutes, 0.5 is 30 minutes, and 0.8 is 48 minutes.
Find which quarter mark the minutes are closest to. Minutes 0 to 7 round to 0.00, 8 to 22 round to 0.25, 23 to 37 round to 0.50, 38 to 52 round to 0.75, and 53 to 60 round to 1.00. This is the seven-minute rule. The converter does it in one press, and in a spreadsheet the formula is MROUND with an increment of 0.25.
Keep three through every intermediate step and round to two only on the final figure. One minute is 0.016666 recurring, so two places is not enough to hold a single minute accurately. Five entries of 7.33 instead of 7.333 lose a minute across a week, and a hundred entries of 0.33 instead of 0.333 lose twenty minutes.
20 minutes is 0.333 decimal hours, because 20 divided by 60 is one third, which recurs forever as 0.333333. Rounded to three places it is 0.333, and rounded to two it is 0.33. The matching value at the other end is 40 minutes, which is two thirds, or 0.667 to three places.
In the United States the Fair Labor Standards Act permits rounding clock punches to a set increment provided the practice is neutral over time and does not consistently work against the employee. A policy that only ever rounds down is the kind that gets challenged. Canadian provincial employment standards generally require that all hours worked are paid, so rounding must never reduce the total.
Convert each day to total minutes, add the integers, then divide once at the end. Five shifts of 7:45, 8:10, 6:55, 8:30 and 7:20 are 465, 490, 415, 510 and 440 minutes, totalling 2,320 minutes. That is 38 hours 40 minutes, and 40 divided by 60 is 0.667, so the decimal total is 38.667 hours.
8.75 hours is 8 hours 45 minutes, because 0.75 multiplied by 60 is 45. A common error is to read it as 8 hours 75 minutes, which would be 9:15 and overstates the time by half an hour. The same rule handles any decimal: 8.5 is 8:30, 8.25 is 8:15 and 8.1 is 8:06.