Hours of Service Calculator — FMCSA HOS Compliance
Track your remaining drive time under FMCSA Hours of Service regulations. Covers the 11-hour drive limit, 14-hour on-duty window, 30-minute break requirement and 70-hour cycle.
⏰ Hours of Service Calculator
How to Use This Calculator
- Enter your shift start time — when you came on duty after your 10-hour off-duty reset.
- Enter current time — to calculate elapsed time in your 14-hour window.
- Enter drive time used — total hours behind the wheel this shift.
- Enter 70-hour cycle usage — total on-duty hours in the last 8 days from your logbook or ELD.
Worked Example
A driver starts at 6:00 AM, it's now 2:00 PM. They've driven 6.5 hours and taken their 30-minute break. Cycle used: 58 hours.
- Elapsed shift: 8 hours into 14-hour window
- Window remaining: 6 hours left in 14-hr window
- Drive remaining: 11 − 6.5 = 4.5 hours
- Cycle remaining: 70 − 58 = 12 hours
- Effective drive: MIN(4.5, 6, 12) = 4.5 hours
The binding constraint is drive time (4.5 hrs). The driver can drive until approximately 6:30 PM before needing a 10-hour reset.
Frequently Asked Questions
Property-carrying drivers: 11 hours driving maximum; 14-hour on-duty window after 10 consecutive off-duty hours; 30-minute break required after 8 hours driving; 70-hour limit in any 8 consecutive days (60-hour/7-day for some carriers). The 34-hour restart resets the 70-hour clock.
Drivers who take at least 34 consecutive off-duty hours can restart their 70-hour/8-day clock. The restart must include two periods of 1:00 AM–5:00 AM. This allows drivers to reset weekly rather than waiting for the 8-day rolling window to clear.
Drivers who stay within 150 air miles of their normal work reporting location and return within 14 hours may use the short-haul exception — they don't need to keep a log if they meet these conditions. CDL holders get 150 air miles; non-CDL property drivers get 150 miles.
Yes — Electronic Logging Devices (ELDs) automatically record drive time, on-duty time, and rest periods. Most ELDs alert drivers when they're approaching limits. Mandatory for most interstate commercial drivers since December 2017.