DOT Hours of Service Calculator
Track your remaining driving and on-duty hours under FMCSA Hours of Service rules. Covers the 11-hour driving limit, 14-hour window, and 70-hour/8-day cycle.
Results
Visualization
How It Works
FMCSA Hours of Service rules under 49 CFR Part 395 govern when property-carrying CMV drivers can drive. Three hard ceilings: 11 hours driving (49 CFR §395.3(a)(3)), a 14-hour on-duty window starting the moment you come on duty (§395.3(a)(2)), and a 60/7 or 70/8 cycle limit (§395.3(b)). On top of those, a 30-minute break is required once 8 cumulative hours of driving have passed without a qualifying interruption (§395.3(a)(3)(ii)). The 14-hour clock does not pause for meals, fueling, or off-duty breaks. Roadside violations show on your DAC report and your carrier CSA score for 24 months.
The Formula
Remaining On-Duty = 14 - On-Duty Hours Today
Remaining Cycle = 70 - Hours Used in 8-Day Cycle
Effective Hours = min(Remaining Driving, Remaining On-Duty, Remaining Cycle)
30-min break trigger: cumulative driving >= 8 hours since last 30+ min non-driving period
Variables
- 11 — 49 CFR §395.3(a)(3) — maximum driving hours after 10 consecutive off-duty
- 14 — §395.3(a)(2) — on-duty window from first on-duty status; cannot be paused
- 70/8 — §395.3(b)(2) — max on-duty hours in any 8-consecutive-day period (carriers operating 7 days/week)
- 60/7 — §395.3(b)(1) — alternative cycle for carriers not operating every day of the week
- 34 — §395.3(c) — consecutive off-duty hours that fully reset the 60/70-hour cycle
- 8/2 or 7/3 — §395.1(g) — sleeper berth split: one period >= 7 hours in berth, the other >= 2 hours off-duty or in berth, totaling >= 10
Worked Example
Driver logs on at 0600 Monday in Atlanta. Drives 5.5 hrs to Knoxville (1130), takes a 30-min break at the TA (covers §395.3(a)(3)(ii)). Resumes 1200, drives 4 hrs to a customer in Bristol (1600). Live unload runs 1.5 hrs (on-duty not driving). Now: driving = 9.5, on-duty = 11.5, 14-hr clock expires at 2000. Has 1.5 hrs of driving capacity left under the 11-hr rule but only 8.5 hrs to bring it home before the 14-hr window closes. Cannot drive again until 0600 Tuesday after a 10-hour reset under §395.3(a)(1). If the driver had used a qualifying 8/2 split (7+ hrs in sleeper after Bristol unload, then a 2-hr off-duty later), the 14-hr clock would effectively extend by the sleeper period.
Practical Tips
- The 14-hour on-duty clock under §395.3(a)(2) cannot be paused with off-duty time alone — only a qualifying 10-hour reset, a 34-hour restart per §395.3(c), or a sleeper-berth split per §395.1(g) extends driving capacity. Watch this number, not the 11-hour limit, to plan your day.
- 30-minute break under §395.3(a)(3)(ii) triggers after 8 cumulative driving hours without an interruption of >= 30 minutes. Off-duty, sleeper, or on-duty-not-driving (post-2020 rule) all satisfy it — fueling and dock time count as long as duty status changes for the full 30.
- 34-hour restart under §395.3(c) is now optional and free of the old 1am-5am window or once-per-week restriction (the 2017 appropriations law repealed those provisions). Useful when you have stacked-up cycle hours but a short or off-duty period of >= 34 hours coming up.
- Sleeper-berth split per §395.1(g)(1)(ii): the 7+ hour period must be in the sleeper berth itself, not off-duty in the bunk. The shorter 2+ hour period can be off-duty, sleeper, or any combination. Neither period counts against the 14-hour window — the only legal way to extend a driving day mid-trip.
- Adverse driving conditions exception under §395.1(b) extends both the 11-hour and 14-hour limits by up to 2 hours when unforeseeable conditions (snow, fog, accident-caused traffic) prevent the run as planned. Knowing about heavy traffic before dispatch does not qualify — must be unforeseeable at start of the shift.
- Personal Conveyance per FMCSA §392.1.4 guidance: only off-duty status, unloaded movement, to the nearest safe rest. PC cannot advance the load toward delivery, even at lawful speed. Loaded movement immediately disqualifies the time as PC and reverts it to driving status.
- ELD violation civil penalties under 49 USC §521(b) and the FMCSA penalty schedule reach $16,864 per violation (2024 inflation-adjusted) and can place the carrier on out-of-service status during roadside inspection. Falsification of records is a separate federal offense under §521(b)(2)(B).
Frequently Asked Questions
What counts as driving time for HOS?
Driving time per 49 CFR §395.2 is all time at the controls of a CMV in operation on a public road, including time stuck in traffic with the engine running. Stationary on-duty time (loading, paperwork, fueling, pre-trip inspection) is on-duty-not-driving — it counts against the 14-hour window and the 60/70-hour cycle but not against the 11-hour driving cap. Yard moves on private property may be logged as on-duty-not-driving if the carrier policy and ELD configuration support it.
Can I extend my 14-hour on-duty window?
Three legal mechanisms: a qualifying sleeper-berth split under §395.1(g) (7+ hours sleeper plus 2+ hours sleeper or off-duty pauses the 14-hour clock during the longer period), the adverse driving conditions exception under §395.1(b) which adds up to 2 hours when unforeseeable conditions block the run, or the short-haul exception under §395.1(e)(1) which extends the window to 16 hours once every 7 days for short-haul drivers. Plain off-duty breaks do not extend the 14-hour clock.
What is the difference between adverse driving conditions and personal conveyance?
Adverse driving (§395.1(b)) is a regulatory exception that lets you keep driving the load past the 11/14 limits when unforeseen conditions (snow squall, accident-caused gridlock, dense fog) prevent completing the run as originally planned. Personal conveyance (§392.1.4 guidance) is off-duty status for movement of an unloaded CMV for the driver personal benefit (commute, finding food, repositioning to rest area) with strict limits — cannot advance the load toward delivery. They serve different purposes and are not interchangeable.
How does the 30-minute break rule work after the 2020 final rule?
The break is triggered after 8 cumulative driving hours since the last interruption of >= 30 minutes. The 2020 final rule (FMCSA-2018-0248) loosened the requirement: the 30-minute interruption can be off-duty, sleeper, or on-duty-not-driving status. Loading, fueling, paperwork, or any non-driving on-duty activity now satisfies the break — driver no longer has to log off-duty if duty status simply changes from driving for the full 30 minutes.
What is the 150 air-mile short-haul exception?
49 CFR §395.1(e)(1) exempts drivers who (1) stay within a 150 air-mile radius of the normal work reporting location, (2) return to that location within 14 consecutive hours of coming on duty, and (3) have at least 10 consecutive off-duty hours between shifts. Qualifying short-haul drivers are not required to keep an ELD-style RODS log under §395.8 — only timecards showing start time, end time, and total hours each shift. The carrier must verify eligibility daily; one violation knocks the driver out of the exception for that day.
Does on-duty-not-driving time count against the 11-hour driving limit?
No. Only actual driving time counts against the 11-hour cap under §395.3(a)(3). On-duty-not-driving (loading, fueling, paperwork, vehicle inspection) does not consume the 11-hour driving cap. However, all on-duty time — driving plus on-duty-not-driving — counts against the 14-hour window under §395.3(a)(2) and against the 60/70-hour weekly cycle under §395.3(b). This is why dock detention is so costly: hours burn down the 14 and 70 without earning any driving capacity.
How are HOS violations enforced and what are the penalties?
Roadside inspectors use ELD records under 49 CFR §395.20-§395.38 and supporting documents (BOLs, toll receipts, fuel receipts, hotel bills) to verify duty status. Violations score on the carrier CSA HOS Compliance BASIC for 24 months and can place the driver out of service for 10 hours when driving over 11 hours. Civil penalties reach $16,864 per violation (2024 inflation-adjusted); willful falsification is a federal crime under 49 USC §521(b)(2)(B) carrying additional fines and possible CDL disqualification under 49 CFR §383.51.