Hours of Service (HOS) Calculator

Federal property-carrier hours-of-service rules restrict driving based on driving hours, elapsed shift time and accumulated duty. Three clocks run at once: the 11-hour driving limit, the 14-hour driving window and the 60- or 70-hour cycle, plus a break after 8 hours of driving. This calculator gives remaining driving time under a simplified plan, assuming no further work beyond driving and the selected break.

How to use this tool

1. Choose your carrier's cycle: 70 hours in 8 days or 60 hours in 7 days.
2. Enter when your shift started after at least 10 hours off duty, and the time now.
3. Enter the hours you have driven this shift and since your last 30-minute break.
4. Enter the on-duty hours you have used in the cycle, including today, and read your remaining time.

Formula

Driving left = min(11 − driven, 14 − hours since shift start, cycle limit − cycle hours used)

Break due after 8 − driving since last break

A 30-minute break consumes half an hour of driving window; an on-duty break also consumes cycle time. The 14-hour rule limits driving, not all work. Adverse extensions require qualifying unexpected conditions, not routine traffic. Ten hours off alone does not reset a used-up cycle.

Example

A driver who came on duty at 06:00 has driven 6 hours without a break and it is now 13:30. That leaves 5 hours under the 11-hour limit, 6.5 hours of the 14-hour window and 18 hours of a 70-hour cycle with 52 used. The break is due after 2 more hours, so the plan is drive until 15:30, take 30 minutes, and drive 3 more hours: 5 hours in all, stopping at 19:00.