Invoice calculators · Updated August 28, 2026
Billable Hours Calculator
Hours and minutes into decimal hours, times your rate — the exact number for the invoice line. No more guessing what 1h 45m is worth. Free, in your browser.
Invoice line total
Minutes to decimal hours
Invoices multiply Qty × Rate, so time has to become a decimal: divide the minutes by 60. 15m = 0.25, 30m = 0.50, 45m = 0.75, and 1h 45m at $85 is 1.75 × $85 = $148.75. In the generator, decimal hours go in the Qty column and your rate in Rate — the line total and the invoice total compute themselves.
Many businesses round time to the nearest increment before billing — 6-minute (0.1h) and 15-minute (0.25h) blocks are the common conventions. Whichever you use, name it once in your terms ("time billed in 15-minute increments") so the math on the invoice never surprises the client.
Billable hours FAQ
Should I bill exact minutes or rounded blocks?
Exact minutes read as precise but produce odd totals; 6- or 15-minute blocks are the professional norm. Rounding up per task is accepted when your terms say so — rounding up per day usually is not.
How do I show hours on the invoice?
One line per work stream, decimal hours in Qty, rate in Rate, and the period in the description ("Design revisions, May 12–16 — 12.75 h"). The generator's editable column labels let you rename Qty to "Hours".
What about a minimum billable time?
Minimum call-out or session times ("first hour billed in full") are standard in trades and consulting — state the minimum in your terms and bill the first block at that size.
