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Time to Decimal Calculator

Convert hours and minutes — or a start and end time — into decimal hours for payroll, timesheets and invoices.

Quick Answer: How Do You Convert Time to Decimal?

To convert time to decimal hours, divide the minutes by 60 and the seconds by 3600, then add them to the whole hours. The formula is decimal hours = hours + minutes ÷ 60 + seconds ÷ 3600. For example, 7 hours 30 minutes is 7 + 30 ÷ 60 = 7.5 hours, and 45 minutes on its own is 45 ÷ 60 = 0.75 hours. This calculator shows every step and works for shift start and end times too.

Enter Time
Optional break (minutes)
Copied!
Result
Decimal Hours
7.5
7 h 30 min
Decimal hours ≠ hours and minutes written with a point. 7.5 hours means 7 hours 30 minutes, not 7 hours 5 minutes. The digits after the point are a fraction of an hour, so 0.5 is half an hour (30 minutes), not 5 minutes.

How to Use the Time to Decimal Calculator

Pick a mode. Use Hours & Minutes to convert a plain duration such as 7 h 30 min or 45 min, adding seconds if you need them. Use Start & End Time to work out a shift from clock times, in either 24-hour or 12-hour format — the calculator handles overnight shifts automatically. Add an optional break to deduct unpaid time, choose how many decimal places you want, then press Convert. Use Copy result to paste the decimal hours straight into a timesheet.

The Time to Decimal Formula

decimal hours = hours + minutes ÷ 60 + seconds ÷ 3600

Because there are 60 minutes in an hour, each minute is 1 ÷ 60 of an hour (about 0.0167). Each second is 1 ÷ 3600 of an hour. Add these fractions to the whole hours and you have the time in decimal form.

Formula & Rule Cheat Sheet

Quick reference

Minutes to decimal: minutes ÷ 60
Seconds to decimal: seconds ÷ 3600
Shift length: end − start − break
Overnight shift: add 24 hours to the end time
Half an hour: 0.5   Quarter hour: 0.25   Three-quarter hour: 0.75

Worked Examples

1. 7 hours 30 minutes

30 ÷ 60 = 0.5
7 + 0.5 = 7.5 hours

2. 8 hours 15 minutes

15 ÷ 60 = 0.25
8 + 0.25 = 8.25 hours

3. 45 minutes only

45 ÷ 60 = 0.75 hours

4. 2 hours 20 minutes (a repeating result)

20 ÷ 60 = 0.3333…
2 + 0.3333… = 2.333… ≈ 2.33 hours (rounded to 2 places)

5. Shift 9:00 AM to 5:30 PM with a 30-minute break

5:30 PM − 9:00 AM = 8 h 30 min = 8.5 hours
8.5 − 0.5 (break) = 8.0 hours

6. Overnight shift 10:00 PM to 6:00 AM

The end time is next day, so add 24 hours: 6:00 → 30:00
30:00 − 22:00 = 8 h = 8.0 hours

Minutes to Decimal Hours Conversion Table

The decimal column is rounded to four places; the last column is the common two-place payroll value.

MinutesDecimal hoursRounded (2 dp)
10.01670.02
50.08330.08
60.10000.10
100.16670.17
120.20000.20
150.25000.25
180.30000.30
200.33330.33
240.40000.40
300.50000.50
360.60000.60
400.66670.67
450.75000.75
480.80000.80
500.83330.83
540.90000.90
550.91670.92
570.95000.95
590.98330.98

Common Times at a Glance

TimeHours & minutesDecimal hours
Quarter hour0 h 15 min0.25
Half hour0 h 30 min0.50
Three-quarter hour0 h 45 min0.75
Short shift1 h 15 min1.25
Standard morning3 h 45 min3.75
Full workday7 h 30 min7.50
Long shift8 h 45 min8.75

Payroll, Timesheet & Contractor Examples

Payroll: a wage system multiplies decimal hours by the hourly rate. A worker who does 38 h 30 min in a week enters 38.5 hours, so at a $30 rate that is 38.5 × 30 = $1,155 before any deductions. Always convert to decimal before multiplying — never multiply by a time like 38:30. Employers and payroll software may use different rounding rules, so always follow your employer's or payroll system's requirements.

Timesheet: if daily entries are 7 h 45 min, 8 h 15 min and 6 h 30 min, convert each to 7.75, 8.25 and 6.5, then add to get 22.5 decimal hours for the three days.

Contractor invoice: a freelancer who logs 3 h 20 min on a task bills 3.33 hours (rounded to two places). At $80 per hour that is 3.33 × 80 = $266.40. Agreeing the rounding rule with the client up front avoids disputes. This is general information, not financial or employment-law advice.

Common Mistakes

Watch out for these:
  • Reading 7.5 hours as 7 hours 5 minutes instead of 7 hours 30 minutes.
  • Dividing minutes by 100 instead of 60.
  • Forgetting to subtract an unpaid break.
  • Not adding 24 hours for a shift that finishes after midnight.
  • Rounding too early in a multi-day total, which drifts the final figure.
  • Mixing 12-hour and 24-hour times without converting first.
Did you know? Decimal hours are sometimes called "industrial minutes" because factory time clocks began using hundredths of an hour early last century to make wage sums easier. One industrial minute is 0.01 hours, or 36 real seconds.
Pro tip. For payroll, keep the exact value through every calculation and round only the final pay figure. If you must round hours, four decimal places keeps a full week within about a third of a second of error.

Real-Life Uses

Converting time to decimal hours is everyday work in payroll and rostering, construction and trade timesheets, truck-driver logbooks, freelance and consulting invoices, project time tracking, manufacturing shift records, and healthcare rostering. Anywhere hours are multiplied by a rate or added into a total, decimal hours make the arithmetic clean.

Practice Questions

Beginner (with answers)

  1. Convert 6 h 30 min to decimal.
  2. Convert 15 minutes to decimal hours.
  3. Convert 3 h 45 min to decimal.
  4. Convert 90 minutes to decimal hours.
  5. Convert 1 h 15 min to decimal.
Show answers

1) 6.5   2) 0.25   3) 3.75   4) 1.5   5) 1.25

Advanced (with answers)

  1. Convert 8 h 20 min to decimal (2 places).
  2. A shift runs 9:00 AM to 5:30 PM with a 45-minute break. How many decimal hours?
  3. Convert 2 h 40 min to decimal (2 places).
  4. An overnight shift runs 11:00 PM to 7:30 AM. How many hours?
  5. Convert 1 h 30 min 45 s to decimal (4 places).
Show answers

1) 8.33   2) 8.5 − 0.75 = 7.75   3) 2.67   4) 8.5   5) 1.5125

🔑 Key Takeaways

  • Decimal hours = hours + minutes ÷ 60 + seconds ÷ 3600
  • 0.25 = 15 min, 0.5 = 30 min, 0.75 = 45 min
  • Some conversions repeat forever, such as 20 min = 0.333… hours
  • For a shift, work out end − start, then subtract the break
  • Convert to decimal before multiplying by an hourly rate

Frequently Asked Questions

How do you convert time to decimal?

Divide the minutes by 60 and the seconds by 3600, then add them to the whole hours. For example, 7 hours 30 minutes is 7 + 30 ÷ 60 = 7.5 decimal hours.

How do you convert hours and minutes into decimal hours?

Keep the hours as they are and divide the minutes by 60, then add the two together. 8 hours 15 minutes becomes 8 + 15 ÷ 60 = 8.25 hours.

What is 7 hours 30 minutes in decimal?

7 hours 30 minutes is 7.5 decimal hours, because 30 minutes is 30 ÷ 60 = 0.5 of an hour.

What is 8 hours 45 minutes in decimal?

8 hours 45 minutes is 8.75 decimal hours, because 45 ÷ 60 = 0.75.

What is 1 hour 15 minutes in decimal?

1 hour 15 minutes is 1.25 decimal hours, because 15 ÷ 60 = 0.25.

How many decimal hours is 30 minutes?

30 minutes is 0.5 decimal hours, since 30 ÷ 60 = 0.5.

How many decimal hours is 45 minutes?

45 minutes is 0.75 decimal hours, since 45 ÷ 60 = 0.75.

How do I convert minutes to decimal hours?

Divide the number of minutes by 60. So 20 minutes is 20 ÷ 60 = 0.3333… hours, which rounds to 0.33 for payroll.

How do I convert seconds to decimal hours?

Divide the seconds by 3600, because an hour has 3600 seconds. 45 seconds is 45 ÷ 3600 = 0.0125 hours.

How do payroll systems calculate decimal hours?

They convert each worked period to decimal hours, subtract unpaid breaks, add the periods together, then multiply the total by the hourly rate. Decimal hours make the multiplication straightforward.

How do timesheets use decimal hours?

Many timesheets record each entry in decimal form — 7.75 instead of 7 h 45 min — so daily and weekly totals can be added directly without carrying minutes over into hours.

What is the formula for time to decimal?

Decimal hours = hours + minutes ÷ 60 + seconds ÷ 3600. Add the fraction of an hour from the minutes and seconds to the whole hours.

Why is 20 minutes 0.33 and not 0.20 in decimal?

Decimal hours are fractions of 60 minutes, not 100. 20 minutes is 20 ÷ 60 = 0.333… of an hour, which rounds to 0.33 — not 0.20.

How do I handle an overnight shift?

When the end time is earlier than the start time, the shift crosses midnight. Add 24 hours to the end time before subtracting. The calculator does this for you and marks the shift as overnight.

Can I convert military time to decimal hours?

Yes. The calculator accepts both 24-hour (military) time and 12-hour time with AM/PM, and both produce the same decimal-hour result.

Is this Time to Decimal Calculator free?

Yes. It is free with no sign-up, works on any device, and runs in your browser so your entries stay private.

References

Last updated: July 2026
Reviewed by the MegaCalcOnline Editorial Team using standard time-conversion principles and trusted educational references. Conversions use exact fractions of an hour, with rounding applied only to the displayed result. This page is for educational purposes and is not financial or employment-law advice.