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🔢 Time

Decimal Time Calculator

Convert hours and minutes to decimal hours and back — 2:30 to 2.5 hours, or 3.75 hours to 3:45 — the conversion payroll and time-tracking need.

HH:MM → decimal
Decimal → HH:MM
Payroll-ready
Both directions
100% Free
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Decimal time — Quick answer

Minutes are sixtieths of an hour — divide by 60, don't read them as hundredths.

decimal = hours + minutes ÷ 60  ·  minutes = (decimal − hours) × 60

Worked example: 2:30 = 2 + 30/60 = 2.5 hours; 3.75 h = 3:45.

Common conversions

HH:MMDecimal
2:302.50
3:453.75
8:158.25
1:061.10

30 minutes = 0.5 hour, not 0.30 — a common payroll slip.

🔢 Decimal Time Calculator

Choose a direction and enter your value.

Result
Also

ℹ️ Minutes are out of 60. 30 min = 0.5 h, not 0.30. This converts one duration — to add durations use the time calculator.

Decimal time expresses minutes as a fraction of an hour, which is what payroll multiplies by a wage. To convert, divide the minutes by 60 and add the hours: 2:30 → 2.5. To go back, the whole number is the hours and the decimal × 60 gives the minutes: 3.75 → 3:45. The trap is that minutes are sixtieths, so 30 minutes is 0.5, not 0.30.

Reviewed: June 20, 2026 · Author: Naveen P N, Founder — AI Calculator · Verified against: minute/60 arithmetic, recomputed in code.

The conversion

HH:MM → decimal
decimal = hours + minutes ÷ 60
Decimal → HH:MM
hours = whole part · minutes = (decimal − hours) × 60

Going to decimal, the minutes become a fraction: 15 minutes is 15/60 = 0.25, 30 is 0.5, 45 is 0.75. Going back, split off the whole hours, then multiply what's left by 60 to recover the minutes. A round decimal like 1.1 gives 0.1 × 60 = 6 minutes, so 1.1 hours is 1:06 — not 1 hour 10 minutes.

Worked examples

2 hours 30 minutes to decimal:

→ decimal
2 + 30/60 = 2.5 hours

3.75 decimal hours to H:MM:

→ H:MM
0.75 × 60 = 45 → 3:45

1.1 decimal hours to H:MM:

→ H:MM
0.1 × 60 = 6 → 1:06

So 2:30 is 2.5, 3.75 hours is 3:45, and 1.1 hours is 1:06. A 7-hour-45-minute shift entered for pay is 7.75 hours.

Frequently Asked Questions

How do I convert hours and minutes to decimal?

Minutes ÷ 60, add hours. 2:30 = 2 + 0.5 = 2.5; 3:45 = 3.75; 8:15 = 8.25.

Decimal hours back to HH:MM?

Whole = hours; decimal × 60 = minutes. 2.5 → 2:30; 3.75 → 3:45; 1.1 → 1:06.

Why is 30 min 0.5, not 0.30?

60 minutes per hour, not 100. 30/60 = 0.5. Reading 8:30 as 8.30 is a common error.

Why does payroll use decimal hours?

Wage × hours is easy with decimals. 7:45 = 7.75 h; at $20/h that's $155.

Does this add times?

No, it converts one duration. Use the time calculator to add/subtract, or the hours calculator for time between times.

Need more time tools?

Explore hours between times, duration math, time cards, add-time and more across the AI Calculator date & time suite.

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