Minute to Decimal Converter

A minute to decimal converter turns time written in hours and minutes — like a timesheet entry of 7:30 — into a single decimal number, like 7.50. The math is straightforward: divide the minutes by 60 and add the result to the hours. Twenty-three minutes is 23 / 60 = 0.3833 hours. Seven hours and thirty minutes is 7 + 30/60 = 7.50 hours. The reason this conversion matters is that almost every payroll system, billing system, and spreadsheet on the planet expects time in decimal hours so it can be multiplied by an hourly rate. A column of 7:30, 8:15, 7:45 can’t be summed by a spreadsheet directly; the same column written as 7.50, 8.25, 7.75 adds up to 23.50 in one click.

The trickiest part of decimal-hour conversion isn’t the arithmetic — it’s the rounding. Most contracts specify a granularity. US salaried payroll typically rounds to the nearest quarter hour (15 minutes); legal and consulting billing often uses the nearest tenth of an hour (6 minutes); some scientific and engineering contracts round to the nearest minute. The rounding granularity has to be applied consistently to each entry — rounding only the total can swallow a half-minute per row that adds up to real money over a week. This tool rounds each row, then sums.

The rounding method matters too. The naive “round half up” rule (7.5 always becomes 8) creates a systematic upward bias when applied to a long timesheet — every :30-ending entry rounds up half-an-hour-equivalent, gaining the employee a few free minutes per week. Banker’s rounding, also called round-half-to-even, breaks ties by rounding to the nearest even multiple of the granularity. In the 1/4 hr mode, that means 7 minutes rounds down to 0 (since 0 is even), 22 minutes rounds up to 30 (since 2 quarters is even), and so on. Across many entries, banker’s rounding averages out to neutral instead of biased. This is also the rule used by Python, NumPy, and IEEE 754 by default, so the numbers match what your downstream spreadsheet would produce if you re-rounded.

The ranges of accepted input formats are designed to match how people actually type time. The dominant format is H:MM — 7:30, 8:15, 0:45. A leading colon is shorthand for under-one-hour entries: :45 means 45 minutes. The Xh Ym form (7h 30m, or compact 7h30m) is also common, especially in exported data from time-tracking apps. Bare numbers (7, 7.5) are always interpreted as decimal hours — not minutes — to avoid the magic-threshold guesswork that some converters use (“if it’s bigger than 60 it must be minutes” rules are a footgun). To enter raw minutes, append m: 30m, 90m. The hint under the rows lists every form.

Beyond payroll, the secondary “Convert minutes” tab handles single-shot unit conversions of the type that show up in homework, cooking, video editing, and back-of-envelope math: type 90 and see at a glance that it’s 1.5 decimal hours, 0.0625 of a day, 5,400 seconds, and 01:30:00 in HH:MM:SS form. There’s no rounding mode in this tab — when someone searches “what is 90 minutes in decimal hours,” they want the exact answer, not the rounded one.

Privacy is the final detail worth stating explicitly. Every calculation in this tool runs locally in your browser. Your timesheet entries are saved to your own browser’s localStorage so a refresh doesn’t blow away an in-progress week, but the data never leaves your device — there’s no server, no API, no analytics on input values. Click the Clear button next to the total to wipe the saved state. If you want to wipe a single device’s stored timesheet without using the button, your browser’s “clear site data” tool does it — the storage key is mtd:timesheet:v1.