Driver Hours & Compliance Log

What this tool does

CM8-102 keeps a duty-by-duty log of driver hours and checks each duty against six limits that you set. For every duty it works out the total duty time from the start and end times, the driving time in hours, the working time, and whether the driving, the duty length, the break taken or the rest taken before the duty fell outside your limits. It then adds driving time up per driver per week and compares that with your weekly limit.

The point of it is early warning. A planner rarely sees a running weekly driving total, and a driver rarely knows they are two hours from a weekly ceiling until they are past it. This puts both on one screen.

Everything runs inside this one file — no account, no upload, no network request — so driver names, routes and hours never leave the computer you are using.

What it is not

This is a monitoring aid. Say that plainly before you rely on anything it produces:

• It is not a tachograph. It records nothing automatically and cannot see what a vehicle actually did.
• It is not an analysis bureau. It does not read tachograph downloads, driver cards, charts or telematics feeds, and it cannot detect a missing record, a card pulled out mid-duty or a duty that was never entered at all.
• It is not the legal record. The record you must keep, retain and be able to produce is defined by the law that applies to you — usually the tachograph data, the driver's card, the charts or a prescribed record sheet. Keep those. This log sits alongside them.
• It does not know your rules. Every limit starts as a placeholder and stays wrong until you replace it.

What it does well is consistent arithmetic on data you already have, which is more than can be said for most spreadsheets used for this.

Setting the limits

Six limits live on the Settings tab. Nothing is assumed about which country you are in, what the vehicle is, what the operation is, or whether the driver is subject to one rule set or several at once. All six are yours to set:

• Maximum daily driving hours — driving time only, within one duty.
• Maximum daily duty hours — start of duty to end of duty, breaks included.
• Driving hours that trigger a break — the amount of driving after which a break becomes compulsory.
• Minimum break once triggered — in minutes, totalled across the duty.
• Minimum rest before duty — hours off duty immediately before the duty starts.
• Maximum weekly driving hours — per driver, per week.

Set them from whatever governs your operation: the law where the vehicle runs, the licence conditions, a customer contract, a collective agreement, or your own policy where that is stricter. Where more than one rule set applies, use the strictest figure among them and say so in the report notes.

Recording a duty

One row is one driver on one working day. Enter the duty start and end as clock times — 06:00 or 6:00 AM both work — and everything else in minutes, because minutes are what tachograph printouts and timesheets give you, and converting by hand is where errors creep in. A duty that ends earlier in the clock than it started is treated as running past midnight, so 21:00 to 05:30 is 8.5 hours, not a negative number.

The tool rejects one combination outright: driving plus other work plus break adding up to more than the time between the duty start and end. That is arithmetically impossible, and it is the commonest data-entry error in a log like this — usually a mistyped end time.

Spell driver names the same way every time. Weekly totals, the driver summary and both driver charts group on the name, ignoring case and surrounding spaces but nothing else — M. Diallo and Diallo M are two different drivers to this tool.

Every formula

Nothing here is hidden. These are the calculations in full:

Two of these deserve a word. Working time deliberately excludes breaks, so it is not the same as duty time; the difference between the two is break plus any waiting you did not count as work. And average daily driving is per duty recorded, not per calendar day — a driver with four duties in a week divides by four, not by seven. Rest days would drag the average down and tell you nothing.

Breaks

The break check is deliberately coarse, and you should know exactly how coarse. It asks one question: once a duty's driving time passes your trigger, did the total break minutes in that duty reach your minimum? It cannot ask when the break was taken, whether it came before or after the trigger point, or whether it was one unbroken period or six five-minute stops. Many rule sets care a great deal about all three.

So treat a passed break check as "nothing obviously wrong" rather than "compliant". A duty with a long enough total break taken entirely at the end of the shift will pass here and fail almost anywhere else. The note field is the right place to record how a break was actually split.

Rest before duty

Rest before duty is the uninterrupted time off duty immediately before the duty began. Enter it in hours — 10.75 rather than 10 hours 45 minutes.

Leave it blank when you do not know it, and the rest check is skipped for that duty rather than assumed to have passed. The breaches chart shows how many duties were actually tested, so a wall of blanks cannot quietly turn into a clean sheet. The first duty after a driver's holiday or rest period is worth entering properly even though it will obviously pass — it keeps the tested count honest.

Weeks and weekly totals

A weekly total is meaningless until you say where the week begins, so that is a setting. Pick the day your week starts on and every weekly figure is recalculated from it. A week is that day plus the following six days; every day is counted, including rest days, weekends and days with no duty recorded — a day with no duty simply contributes nothing.

Weekly driving is the sum of driving minutes for one driver across those seven days. Two things about it:

• It is a whole-register figure. Filters change which weeks are shown but never what a week totals, so filtering to a single vehicle cannot make a driver's week look lighter than it was.
• It is only as complete as the register. A driver's duties in another vehicle, at another depot or for another employer are in the total only if somebody entered them.

The weekly chart plots the highest single driver in each week, not the fleet total. A fleet total compared with a per-driver limit would be a meaningless number that gets worse as you hire people, and it is precisely the kind of mistake this tool exists to avoid.

Night work and double manning

Both are recorded and neither changes any calculation. That is on purpose. Where you operate, night work may attract a shorter duty limit and double manning may allow a longer one or a differently structured rest period — or neither may apply. Guessing which, and quietly applying it, would produce a confident wrong answer.

So use the two boxes as flags. Filter or sort by them, and where a double-manned duty is flagged for rest or duty length, check it against the rule that actually applies before treating it as a breach. Equally, if night work carries a tighter limit for you, a night duty that passes here may still be a problem.

Reading the charts

The tiles and charts follow whatever the filters show, except the weekly figures described above. Four charts, four different questions:

• Driving hours by driver — total hours in the period, with each driver's longest single duty and the number of duties over the daily limit written alongside. A short bar with breaches on it is a worse sign than a long bar with none.
• Breaches by type — which of the four checks is failing. Break and rest failures are usually a planning problem; daily driving failures are usually an over-optimistic schedule.
• Highest weekly driving — the busiest driver each week against your weekly limit.
• Breaches by driver — one duty can contribute up to four, so this ranks by severity as well as frequency.

The Limit breaches table is the one to act on. It gives the date, the driver, the vehicle, which limit was passed, what was recorded, what the limit was and by how much it was exceeded — enough to take to the underlying record and check.

Different vehicle classes

Limits commonly differ by vehicle class, and a single set of settings cannot express two rule sets at once. Every duty carries a vehicle class, and the class is a filter, so there are two sound ways to work:

• Filter to one class, set the limits for that class, print, then repeat. Each printed report then states the filter in force in its header, so the report and the limits it was produced under always travel together.
• Set every limit to the strictest figure across all the classes you run. You will see breaches that are not breaches for the lighter class, but you will never miss a real one.

What you must not do is set the limits for one class and read the numbers for another. Nothing on screen will warn you — the limits are just numbers you typed.

Printing and sharing

Print Report produces a report from whatever the current filter shows: header, the six headline figures, all four charts, the breach table, the driver summary, the full duty register and your closing notes. Print to PDF to circulate it.

Put the source of your limits in the closing notes every time. A driver-hours report with no statement of which limits were applied is not much use to the person reading it, and is actively misleading if they assume the wrong ones.

Saving your work

Duties, settings and the report header are written to this browser's local storage as you type, and the toolbar shows the time of the last save. That storage belongs to one browser on one computer: another browser, a private window, a second machine or a clean-up tool that clears site data will not have it.

Treat Export .json as the real save — one file containing everything, which Import .json restores anywhere. Export CSV gives you the register for spreadsheet work, including every derived value and every filtered record, not only those drawn on screen. Reset asks twice, then erases everything this tool has stored. There is no undo.

The log names identifiable people and describes their working time, so treat exports as confidential and keep them for no longer than you need to.

Accuracy & disclaimer

This tool calculates from what you type and compares the result with limits you chose. It cannot tell whether the minutes are right, whether a duty is missing, whether the driver was subject to a different rule that day, or whether the limits themselves are the correct ones. A clean sheet here is evidence of nothing except that the numbers entered were inside the numbers set.

Driver-hours rules, record-keeping duties, retention periods and the treatment of night work, double manning, breaks and rest differ by country, by vehicle class and by type of operation, and more than one rule set can apply to the same journey. This is an internal monitoring and calculation aid, not legal advice, not a compliance certification, and not a substitute for the tachograph, the analysis of it, or whatever record the law where you operate requires you to keep.