Billable hours calculator

Convert hours and minutes to decimal hours, round each entry up to 6 or 15 minutes, add a minimum and an hourly rate. Free, in your browser.

How the rounding works

Each entry is rounded up to the next step, then the minimum applies: with 15-minute rounding and a 30-minute minimum, a 5-minute call bills 30 minutes and a 37-minute call bills 45. Rounding each entry gives a higher total than rounding the month once; the calculator shows both, so you can choose the rule to write in your quote. The guide to billing clients from Google Calendar explains which rule fits which client.

Decimal hours are minutes divided by 60: 37 minutes is 37 ÷ 60 = 0.62 hours. Billing in tenths of an hour, common with lawyers and consultants, rounds each entry up to the next 6 minutes.

Minutes to decimal hours

Minutes	Hours	Minutes	Hours	Minutes	Hours	Minutes	Hours
1	0.02	16	0.27	31	0.52	46	0.77
2	0.03	17	0.28	32	0.53	47	0.78
3	0.05	18	0.30	33	0.55	48	0.80
4	0.07	19	0.32	34	0.57	49	0.82
5	0.08	20	0.33	35	0.58	50	0.83
6	0.10	21	0.35	36	0.60	51	0.85
7	0.12	22	0.37	37	0.62	52	0.87
8	0.13	23	0.38	38	0.63	53	0.88
9	0.15	24	0.40	39	0.65	54	0.90
10	0.17	25	0.42	40	0.67	55	0.92
11	0.18	26	0.43	41	0.68	56	0.93
12	0.20	27	0.45	42	0.70	57	0.95
13	0.22	28	0.47	43	0.72	58	0.97
14	0.23	29	0.48	44	0.73	59	0.98
15	0.25	30	0.50	45	0.75	60	1.00

6-minute increments chart

Minutes worked	Billed (hours)
1–6	0.1
7–12	0.2
13–18	0.3
19–24	0.4
25–30	0.5
31–36	0.6
37–42	0.7
43–48	0.8
49–54	0.9
55–60	1.0

Questions

How do I convert minutes to decimal hours?

Divide the minutes by 60. 15 minutes is 0.25 hours, 20 minutes is 0.33, 45 minutes is 0.75. In a spreadsheet, a duration stored as a time (1:30) becomes decimal hours with =A2*24.

What are 6-minute increments?

Billing in tenths of an hour: every started block of 6 minutes counts as 0.1 hours. A 7-minute call bills 0.2 hours, a 13-minute call 0.3.

Should I round each entry or the total?

Most professionals round each entry and say so in their quote or contract. Whatever you choose, apply the same rule every month. The table above shows the difference for your own entries.

Can it take my hours from Google Calendar?

This calculator works on what you type. To total the hours already in your calendar, use the Google Calendar hours calculator; to have them rounded and billed every month, Calendar Timesheet does it in Google Sheets.