DOT Hours of Service Calculator

How to use this calculator

1. Pick your weekly cycle rule (60-hour/7-day or 70-hour/8-day) and whether you have taken a 34-hour restart.
2. Enter how your day has gone so far: hours driven today, on-duty (not driving) hours, and how long it has been since you came on duty.
3. Enter how long you have driven since your last 30-minute break and how many on-duty hours you have already used in your current cycle.
4. Read your driving time remaining, the four clocks, and the plain-language limiting factor that tells you which rule is holding you back.

How it works

This calculator applies the federal FMCSA hours-of-service limits in 49 CFR 395.3 for property-carrying commercial drivers and tells you how much you can legally drive right now. It does not model passenger-carrying drivers, who have different limits.

You pick your weekly cycle rule and whether you have taken a 34-hour restart, then enter how your day has gone so far. From those numbers the tool checks four clocks at once:

• The 11-hour clock limits total driving in a shift. You may drive a maximum of 11 hours after 10 consecutive hours off duty.
• The 14-hour clock limits how long after coming on duty you may drive at all, and it keeps running even during meals and rest breaks.
• The 30-minute break clock requires a break once you have driven 8 cumulative hours.
• The 60- or 70-hour cycle clock limits your total on-duty time across the rolling week.

Your driving time remaining is the smallest of those four caps, each floored at zero. The tool also names which clock is holding you back, so you know whether you need a 30-minute break, a 10-hour reset, or a 34-hour restart. These limits are published in the official FMCSA Hours of Service visor card and the FMCSA summary of hours of service regulations.

The figures are estimates for trip planning only. Your ELD and your carrier’s policy are the official record. This tool leaves out sleeper-berth splits, short-haul exceptions, and adverse-driving extensions to stay simple and predictable.

Examples

70-hour/8-day driver, 6 hours driven, 8 hours into the shift, no break yet. If you input 6 hours driven, 8 hours since coming on duty, 6 hours of driving since your last break, and 40 cycle hours used, the tool returns 2 hours of driving time remaining. The 30-minute break rule is the binding limit, because you may drive only 2 more hours (8 minus 6) before a break is due, and that is less than your 11-hour and 14-hour room.

60-hour/7-day driver near the end of the 14-hour window. If you input 9 hours driven, 13 hours since coming on duty, 3 hours since your last break, and 55 cycle hours used, the tool returns 1 hour of driving time remaining. The 14-hour window is the binding limit, because only 1 hour is left in the window (14 minus 13) even though your 11-hour and break clocks have more room.

Driver who just took a 34-hour restart, starting fresh. If you select Yes for the restart with all daily clocks at zero, the cycle resets to the full 70 hours and the tool returns 8 hours of driving time remaining. The 30-minute break rule caps you at 8 hours, because a break is due after 8 cumulative driving hours, even on a fresh 11-hour clock.

The four HOS clocks at a glance

Property-carrying drivers run on four federal clocks at once, set out in 49 CFR 395.3. Each clock has its own limit, its own reset, and its own slice of your day that it counts.

Clock	Limit	What resets it	What it counts
11-hour driving limit	11 hours	10 consecutive hours off duty	Driving time only
14-hour on-duty window	14 hours	10 consecutive hours off duty	All time after you come on duty; it does not pause for breaks
30-minute break	Required after 8 cumulative driving hours	Any 30 consecutive minutes not driving	Cumulative driving time since your last break
60/70-hour cycle	60 hours in 7 days, or 70 hours in 8 days	34 or more consecutive hours off duty	All on-duty time across the rolling week

How the 34-hour restart resets your weekly cycle

The 34-hour restart is an optional way to clear your weekly cycle and start over with a full 60 or 70 hours (49 CFR 395.3). It works in three stages:

• You reach the cycle cap. Your on-duty time hits 60 hours over 7 days or 70 hours over 8 days, depending on your carrier’s cycle, and you can no longer drive on that cycle.
• You take 34 or more consecutive hours off. This time can be off duty, in the sleeper berth, or a combination of the two, as long as it runs for at least 34 hours without a break.
• You resume with a full cycle. Once the 34 hours are complete, your weekly cycle resets to the full 60 or 70 hours.

The restart resets only the weekly cycle. It does not reset your 11-hour and 14-hour daily clocks, which still need 10 consecutive hours off duty to start fresh (49 CFR 395.3).

Sleeper-berth split options (7/3 and 8/2)

The split-sleeper provision for property carriers lets you divide your required off-duty time into two rest periods instead of one (49 CFR 395.1). The two periods must meet these conditions:

• They total at least 10 hours. Added together, the two rest periods must equal the full 10-hour off-duty requirement.
• One period is at least 7 consecutive hours in the sleeper berth. This is the longer of the two rest periods.
• Neither period is shorter than 2 hours. This sets the floor for the second period.

These rules produce the two common pairings, 7/3 and 8/2. The longer of the two periods pauses your 14-hour window, which can give you more usable hours later in the shift. This calculator does not model split-sleeper rest, so its results stay conservative when you use one (49 CFR 395.1).

Short-haul and adverse-driving exceptions

Two exceptions in 49 CFR 395.1 come up most often for property drivers. This calculator does not model either one, so check your ELD and carrier policy when one applies.

150 air-mile short-haul exception

This exception covers drivers who stay close to home base. You must operate within 150 air-miles of your work-reporting location and return there within 14 hours. Drivers who qualify do not need an electronic logging device or a logged 30-minute break (49 CFR 395.1).

Adverse-driving-conditions exception

This exception covers weather or traffic you could not have known about when you started the trip. It lets you add up to 2 hours of driving time and up to 2 hours to your 14-hour window to finish the run safely (49 CFR 395.1).

What the data says

If you drive for a living, you already know the worst part of the day is watching the 14-hour clock run while you sit. Time stuck at a dock burns drive time you never get back, and a badly timed restart can screw up your next week. The clock can feel arbitrary when you are not the one who is tired. The crash data is why it exists at all.

Federal investigators found driver fatigue was associated with roughly 13 percent of the large-truck crashes in the FMCSA Large Truck Crash Causation Study, a sample of 967 crashes investigated between 2001 and 2003 (National Academies of Sciences, via NIH National Library of Medicine). That is more than 1 in 8. The rules cap your hours before you reach that point, not after.

Safety officials tie any gap in those rules straight to crash risk. After a 2023 review of hours-of-service exemptions, the chair of the National Transportation Safety Board put it plainly:

“Drivers operating under an hours-of-service exemption are at a greater risk of fatigue: an unacceptable and avoidable danger to every road user.”

Jennifer Homendy, Chair, National Transportation Safety Board, in an NTSB press release.

How often fatigue gets blamed depends on how you count it. Crash codes alone tell a smaller story: only about 1.5 percent of fatal large-truck crashes in 2013 were officially attributed to a tired or sleeping driver, a figure researchers consider biased low because fatigue is hard to detect after the fact (National Academies of Sciences, via NIH National Library of Medicine). The spread across methods is the point.

Source or study	Fatigue attribution	Notes
FARS coded data (2013)	1.5% of fatal large-truck crashes	Considered biased low, since fatigue is hard to detect
LTCCS (2001 to 2003)	13% of crashes associated with fatigue	Sample of 967 crashes, 1,127 trucks
NTSB study (1987 to 1988)	31% of fatal-to-driver truck crashes	56 of 182 crashes, 8 states
CRS and FMCSA (2020)	Up to 20% of bus and large-truck crashes	Broad estimate

Figures compiled by the National Academies of Sciences, via NIH National Library of Medicine; the 20 percent estimate is from the Congressional Research Service report R46276. Fatigue is hard to measure, which is exactly why the rules cap hours rather than wait to catch tired drivers after a crash.

A few mistakes come up again and again in driver forums, and they are worth flagging:

• People commonly forget that the 14-hour clock keeps running even when you go off duty or into the sleeper, so a long wait at a dock eats drive time you cannot recover.
• A common mix-up is the 8/2 and 7/3 sleeper-berth splits. Drivers treat them as fixed blocks, assume a partial break must be followed by a full 8 hours, or invent splits like 6/4 that do not qualify.
• People often expect the clocks to run in sequence and add them up, when the 11-hour driving limit, the 14-hour window, and the 60/70-hour cycle all tick at the same time.

What this tool does that others don’t

• It includes the 60/70-hour cycle limit. The official FMCSA ETHOS tool states that it does not cover the weekly cycle limits, so you cannot see your remaining cycle hours there. This calculator shows the cycle clock alongside the 11-hour, 14-hour, and break clocks.
• It names the single binding limit. Many tools show separate numbers but never tell you which limit is the constraint right now. This tool surfaces one driving-time-remaining figure as the minimum of all caps, plus a plain-language reason.
• It stays focused. Other tools pile on 15 to 20 inputs for split sleeper segments, air miles, and team drivers, with no worked example. This calculator uses a few inputs for the core property-carrier case and shows you worked examples.

Frequently asked questions

What are the FMCSA hours of service limits for property-carrying drivers?

There are four core limits. You may drive a maximum of 11 hours after 10 consecutive hours off duty. You may not drive beyond the 14th consecutive hour after coming on duty. You must take a 30-minute break after 8 cumulative hours of driving. And you may not be on duty more than 60 hours in 7 days or 70 hours in 8 days, depending on your carrier’s cycle.

What is the 14-hour rule and does it stop for breaks?

The 14-hour rule means you cannot drive after the 14th consecutive hour following your last 10-hour off-duty period. Critically, this clock does not pause for meals, fuel stops, or rest breaks. The only common exception is a qualifying sleeper-berth split, which can extend the window but is not modeled in this basic calculator.

When is the 30-minute break required?

The 30-minute break is required once you have accumulated 8 cumulative hours of driving time since your last break of at least 30 minutes. It is triggered by driving time, not on-duty time, and can be satisfied by any 30 consecutive minutes not driving, including off-duty, sleeper-berth, or on-duty-not-driving time.

What is the difference between the 60-hour and 70-hour cycle?

Carriers that do not operate every day of the week typically use the 60-hour/7-day cycle, which caps your on-duty time at 60 hours over any 7 consecutive days. Carriers that operate every day of the week use the 70-hour/8-day cycle, capping on-duty time at 70 hours over any 8 consecutive days. Your carrier assigns which cycle applies to you.

How does the 34-hour restart work?

If you take at least 34 consecutive hours off duty (or in the sleeper berth, or a combination), your weekly cycle resets to a full 60 or 70 hours. This is optional; it is a way to free up cycle hours rather than waiting for hours to roll off the back of the 7- or 8-day window.

What is the difference between driving time and on-duty time?

Driving time is the time you spend operating the vehicle. On-duty time includes driving plus all other work such as loading, unloading, inspections, fueling, and paperwork. The 11-hour limit applies only to driving, while the 14-hour window and the 60/70 cycle count all on-duty time.

What happens if I violate hours of service rules?

HOS violations can result in being placed out of service at roadside, federal and state fines, lower carrier and driver safety scores (CSA), and potential liability in the event of a crash. Your ELD records the violations automatically, so the data is part of the official compliance record.

Do these hours of service rules apply to passenger-carrying drivers?

No. Passenger-carrying drivers have different limits: a 10-hour driving limit (after 8 hours off duty), a 15-hour on-duty window, and the same 60/70-hour cycle figures. This calculator models property-carrying limits only; passenger-carrying drivers should not rely on these results.

Does this calculator handle sleeper-berth splits or short-haul exceptions?

No. To stay simple and predictable, this tool does not model the sleeper-berth split provisions, the 150 air-mile short-haul exemption, the 16-hour short-haul exception, or the adverse-driving-conditions extension. Those provisions can change your available hours, so consult your ELD and carrier policy when they apply.

Is this DOT hours of service calculator legally binding?

No. It is a planning aid only. Your electronic logging device (ELD) is the official record of duty status, and your carrier’s safety policy may be stricter than the federal minimums. Always verify against your ELD and dispatch before driving.

Sources

• eCFR :: 49 CFR 395.3, Maximum driving time for property-carrying vehicles
• FMCSA Hours of Service (HOS) Regulations visor card (FMCSA-MCE-20-009, August 2020)
• Summary of Hours of Service Regulations | FMCSA