Hours of Service Math
FMCSA 49 CFR 395 drive time, 14-hour window, 70/8 cap, and 30-min break.
Example
You enter
- Profile property_70_8
- Events kind on_duty, hours 0.5; kind drive, hours 5; kind off_duty, hours 0.5; kind drive, hours 4
- Weekly on-duty already used (hr) 30
You get
- Drive remaining 2
- On-duty remaining (14 hr window) 4.5
- Weekly remaining 30.5 hr
- Drive used 9
- On duty used 9.5
- 30-min break ok
Details, formula, and sources
FMCSA 49 CFR 395.3: 11-hour driving limit, 14-hour on-duty window, 30-min break required after 8 cumulative hours of driving without a 30-min interruption, and either 70 hours / 8 days or 60 hours / 7 days depending on carrier election.
FMCSA 49 CFR 395.3 by section.
Free at ecfr.gov.
Math aid for personal verification. The ELD on the truck and the carrier tariff are the legal record. State limits may be lower than federal.
Field names used by the API: profile, events, weekly_on_duty_used_hr, drive_remaining, on_duty_remaining, weekly_remaining, drive_used, on_duty_used, needs_break
- Property-carrying CMV true (passenger-carrying CMVs use 49 CFR 395.5)49 CFR 395
- Default 8-day rolling cycle 70 hr / 8 days unless user supplies the 60 hr / 7 day election49 CFR 395.3(b)