Hours to minutes:
convert decimal hours and clock time

How many minutes are in an hour?

An hour has 60 minutes, so you convert hours to minutes by multiplying by 60. Two hours is 120 minutes, five hours is 300 minutes, and a full 8-hour day is 480 minutes.

The factor is simple. The difficulty comes from how the number of hours is written. Timesheets, payroll software and project trackers often show hours as decimals, such as 7.75, while a clock or a call log shows 7 h 45 min.

Decimals exist because they are easy to add. 2.5 + 1.75 + 3.25 = 7.5 hours needs no carrying, while 2 h 30 min + 1 h 45 min + 3 h 15 min makes you carry every time the minutes pass 60.

Both forms describe the same time, but you have to turn the decimal part into minutes before you can read it as a clock time. That conversion is the main subject of this guide.

Durations you already know are good test cases. A 2 h 35 min flight is 155 minutes, and a film of 2 h 18 min is 138 minutes. Try the conversion on those first and check your result against the clock.

If you are working with even smaller units, such as video lengths or lap times, the minutes to seconds article follows on from this one.

Hours to minutes formula for decimal and clock hours

For a decimal such as 2.75 hours, multiply the whole thing by 60: 2.75 × 60 = 165 minutes. To show the clock form, divide 165 by 60 to get 2 hours with 45 minutes left over.

1. 1Write the time as a decimal, for example 2.75 hours.
2. 2Multiply by 60 to get total minutes: 165.
3. 3Divide by 60 and keep the whole number as hours: 2.
4. 4The remainder is the minutes: 165 − 120 = 45, so 2 h 45 min.

• 1/4 hour = 15 minutes
• 1/3 hour = 20 minutes
• 1/2 hour = 30 minutes
• 2/3 hour = 40 minutes
• 3/4 hour = 45 minutes

Thirds are awkward in decimals. Twenty minutes is 0.333... hours, which is why timesheet tools round to a set step. Quarters are tidy by comparison, because 0.25, 0.5 and 0.75 are exact.

To go the other way, divide the minutes by 60. Ninety minutes is 1.5 hours, and 45 minutes is 0.75 hours. Note that 45 minutes is not 0.45 hours.

Worked example: 6.4 hours on a timesheet

A freelancer's tracker shows 6.4 hours for a task. The client invoice needs hours and minutes.

Reverse the same job: a call of 1 h 50 min is 110 minutes, so its decimal is 110 ÷ 60 = 1.83 hours. If your tool bills to the nearest quarter hour, that rounds to 1.75, since 1.83 is closer to 1.75 than to 2.00.

The slip is common because 0.4 looks like 40. In reality, 0.4 of an hour is 24 minutes, while 40 minutes would be 0.67 of an hour.

Decimal hours chart

The first row shows how fine decimal hours can be. Many timesheet tools record in tenths of an hour, which are 6-minute blocks. A task that takes 20 minutes is therefore billed as 0.3 hour, or 18 minutes, under a rounding rule that rounds to the nearest tenth.

Pay and billing by the minute

Converting hours to minutes matters for hourly pay and billing. At ₹480 per hour, one minute is worth ₹8, and 45 minutes is 45 × ₹8 = ₹360. The same figure comes from 0.75 × ₹480.

Now work out a shift from the clock. Someone clocks in at 9:15 and out at 17:45, with a 45-minute break.

1. 1From 9:15 to 17:45 is 8 h 30 min, which is 510 minutes.
2. 2Subtract the 45-minute break: 510 − 45 = 465 minutes.
3. 3Divide by 60 to get decimal hours: 465 ÷ 60 = 7.75 hours.
4. 4At ₹480 per hour, pay is 7.75 × 480 = ₹3,720.

Always check whether the break is paid before deducting it, because policies differ.

A per-minute rate is handy for short jobs. At ₹600 per hour, a minute is ₹10, so a 12-minute call is ₹120. Convert the rate once and multiply by the minutes, instead of turning every call into decimal hours.

Minutes in a day, a week and a month

Larger totals are useful for planning and for subscriptions. A day has 24 × 60 = 1,440 minutes, and a week has 7 × 1,440 = 10,080 minutes.

A 40-hour working week is 2,400 minutes, and a month of 22 working days of 8 hours is 176 hours, or 10,560 minutes. If a meeting takes 30 minutes, it uses 1/80 of a 40-hour week.

Commutes add up faster than people expect. A 1 h 20 min trip each way is 160 minutes a day, and over 22 working days that is 3,520 minutes, or about 58.7 hours.

Rounding rules should be stated whenever minutes are billed. Rounding every entry up to the next quarter hour, to the nearest tenth, or not at all can change a month's total by several hours, so agree the rule before the work starts.

Mistakes with hours to minutes

• Reading decimal hours as clock minutes. 1.30 hours is 78 minutes, not 90, and 1 h 30 min is 90 minutes.
• Using 100 as the factor. Time is base 60, so 2.5 hours is 150 minutes, not 250.
• Crossing midnight without adding 24 hours. A shift from 22:00 to 06:00 is 8 hours, not −16.
• Forgetting unpaid breaks, or counting them twice.
• Adding clock times as if they were decimals. 1 h 45 min + 2 h 30 min is 4 h 15 min, not 3.75 hours.

When in doubt, convert everything to minutes, do the sums, and convert back at the end. It is the one method that never needs a special rule.