How to Convert Time to Decimal Hours in Excel
Payroll and timesheets run on decimals — 8 hours 30 minutes is 8.5, not 8.30. Excel stores a time as a fraction of a day, so the conversion is a multiplication once you know the trick, and totals past 24 hours need a special format. Here's both directions.
Last updated: September 2026
| Duration | Decimal hours | |
|---|---|---|
| 8:30 | → | 8.5 |
| 36:15 | → | 36.25 |
Method 1 — multiply by 24
- A time value is a fraction of a day, so
=A2*24gives decimal hours (8:30 → 8.5). - Use
*1440for minutes or*86400for seconds. - Format the result cell as Number — otherwise Excel shows it back as a time.
Method 2 — totals past 24 hours
Summing durations that exceed a day (37:30 of machine time) wraps to 13:30 with the default format. Fix it by formatting the total as [h]:mm — the square brackets tell Excel not to roll over at 24. Going the other way, =A2/24 turns decimal hours back into a time value.
The 1-click way — Tellsheet
Duration Converter does both directions across a whole column. Time → decimal turns 8:30 (or the Excel time behind it, or a 36:15 that runs past a day) into 8.5 hours, minutes, or seconds to the precision you choose. Decimal → h:mm:ss turns 37.5 back into 37:30:00, showing totals beyond 24 hours without the format fiddling. Fully offline, previewed before it writes. Pairs with Batch Calculate and Unit Converter.
Frequently asked questions
How do I convert time to decimal hours?
=A2*24, or Tellsheet's Duration Converter "time → decimal" for a whole column.
How do I add hours past 24?
Format the total as [h]:mm, or use the Duration Converter's h:mm:ss output.
How do I go from decimal back to time?
=A2/24 formatted as time, or the "decimal → h:mm:ss" mode.
Does it read text like "8:30"?
Yes — it reads both real time values and clock-style text.
Related Excel guides
Convert timesheets in one click
Duration Converter turns 8:30 into 8.5 and back — past 24h without the format tricks.
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