Each limit, measured
Windows
Assumptions used
Important — read before relying on this result
This calculator is an unofficial planning aid and is not a substitute for your ELD, your carrier policies, or current FMCSA requirements. Verify your schedule and the applicable rules before relying on the result.
How this calculator works
Three separate limits cap your driving at any given moment, and they run simultaneously. Whichever runs out first is the one that stops you — which is why drivers who track only the 11-hour limit get caught out by the window, and drivers who track only the day get caught out by the cycle.
This calculator measures all three at once and reports the smallest. It also tells you which limit is binding, so you know what you are actually up against rather than just seeing a number.
Driving limit
Up to 11 hours of driving after 10 consecutive hours off duty. Driving means the vehicle in motion — not loading, fuelling or paperwork.
Driving window
No driving beyond the 14th consecutive hour after coming on duty. Off-duty time inside the day does not push this deadline back.
Required break
A 30-minute non-driving break once you have driven 8 cumulative hours without one. Any non-driving 30 consecutive minutes satisfies it.
Weekly cycle
60 on-duty hours in 7 days, or 70 in 8, depending on your carrier. A 34-hour off-duty period restarts it.
The calculation
driving left = the LOWEST of: driving limit − driving already done 14-hour window − hours elapsed since coming on duty cycle limit − on-duty hours used in the cycle
Everything else on this page is detail around that one line. The limits do not add up or average out — they are three independent ceilings, and you sit under the lowest of them.
The 14-hour window is the one that catches people
This is worth stating on its own because it is counter-intuitive and it costs drivers hours. The window runs from the moment you come on duty and it does not stop. A two-hour wait at a receiver does not pause it. Lunch does not pause it. A nap in the bunk does not pause it.
Fourteen hours after you started, you cannot drive — even if you have only driven six of them. The only thing that changes this is a qualifying sleeper berth split, which is why the Sleeper Berth Calculator exists as a separate tool.
Worked example
You came on duty at 6:00 AM. You have driven 6 hours, spent 1.5 hours on duty not driving, taken a 30-minute break, and used 42 of your 70 cycle hours.
| Limit | Used | Remaining |
|---|---|---|
| Driving (11h) | 6h 00m | 5h 00m |
| Window (14h) | 8h 00m elapsed | 6h 00m |
| Cycle (70h) | 42h 00m | 28h 00m |
The driving limit is the binding constraint here at 5 hours, so that is the figure that matters. The window would let you keep going for another hour after that, and the cycle is nowhere near the issue today — but it will be by the end of the week.
Adverse driving conditions
When conditions you could not reasonably have known about beforehand slow you down — unforecast snow, an unexpected closure, a crash that shuts the interstate — both the 11-hour driving limit and the 14-hour window may be extended by up to 2 hours.
The key phrase is could not reasonably have known about. Heavy traffic you should have anticipated on a Friday afternoon is not adverse conditions. A forecast storm you drove into is not either. This is for genuine surprises, and it is worth being conservative about, because it is the kind of judgement an auditor will second-guess.
Where drivers lose hours
Treating breaks as free
Every minute inside the 14-hour window costs window, whether you are driving, waiting or sleeping in the bunk.
Missing the 8-hour break trigger
The break is required after 8 cumulative driving hours, not 8 hours on duty. It is easy to hit without noticing.
Ignoring the cycle until Thursday
The weekly limit is invisible for three days and then suddenly the only thing that matters.
Assuming the restart is 34 hours of anything
It must be 34 or more consecutive hours off duty. A broken 34 does not restart the cycle.
Claiming adverse conditions loosely
It is a narrow exception for genuinely unforeseeable conditions, not a general allowance for a slow day.
Forgetting on-duty-not-driving time
Loading, inspections and paperwork all consume the window and the cycle even though the truck never moves.
Short-haul and other exceptions
Drivers operating within a 150 air-mile radius of their normal reporting location, and returning there within 14 hours, may qualify for the short-haul exception — which changes record-keeping requirements. Agricultural operations, driveaway-towaway and a handful of other categories have their own provisions.
This calculator applies the standard property-carrying rules and does not model any exception. If you operate under one, your terms govern.
Frequently asked questions
What is the 14-hour rule?
You may not drive beyond the 14th consecutive hour after coming on duty, following 10 consecutive hours off duty. The critical detail is that off-duty time taken during the day does not push that deadline back — a two-hour wait at a receiver costs you two hours of window.
When do I need the 30-minute break?
After 8 cumulative hours of driving without at least a 30-minute interruption. Any non-driving 30 consecutive minutes satisfies it: off duty, sleeper berth, or on duty not driving. Note that the trigger is driving hours, not hours on duty.
What is the difference between the 60/7 and 70/8 cycles?
They are two versions of the same weekly limit — no driving after 60 on-duty hours in 7 consecutive days, or 70 in 8. Which applies depends on whether your carrier operates vehicles every day of the week.
How does the 34-hour restart work?
A period of 34 or more consecutive hours off duty restarts your weekly cycle. The hours must be consecutive; a broken 34 does not count.
When can I use adverse driving conditions?
When conditions you could not reasonably have known about beforehand slow you down — unforecast weather, an unexpected closure, a crash blocking the road. It extends both the driving limit and the window by up to 2 hours. Traffic you should have anticipated does not qualify.
Does time on duty not driving count against my limits?
It counts against the 14-hour window and against your weekly cycle, but not against the 11-hour driving limit. Loading, inspections and paperwork all consume window even though the truck never moves.
Why does the calculator show three different numbers?
Because three separate limits run at the same time and any of them can stop you. The figure that matters is the lowest, and the calculator tells you which one is binding so you know what you are actually up against.
Does this replace my ELD?
No. It is a planning aid. Your ELD and your record of duty status are the authoritative record, and this calculator has no access to either.
Does the sleeper berth provision change these numbers?
It changes how the 14-hour window is counted, and only when a qualifying pair is used. Everything else stays the same. Use the Sleeper Berth Calculator for that scenario.
What about the short-haul exception?
Drivers operating within a 150 air-mile radius of their normal reporting location and returning within 14 hours may qualify, which changes record-keeping requirements. This calculator applies the standard rules and does not model any exception.
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