The breach is never in the shift. It is in the gap.
Drawing a rota grid is easy, and every free rota tool does it. What none of them tells you is the thing that is actually wrong with the week you just built, because the problem is not visible in any of the blocks you drew. It is in the space between two of them.
Friday 14:00 to 22:00
Saturday 06:00 to 14:00Two perfectly ordinary eight hour shifts. Eight hours apart, and unlawful.Regulation 10 of the Working Time Regulations 1998 gives an adult worker eleven consecutive hours of rest in each twenty four hour period, and this week gives eight. The pattern is common enough in hospitality, care and manufacturing to have a nickname, and it survives because a grid shows the blocks and hides the space.
So this tool checks the gaps first and the shifts second. Every gap in the week is measured from the end of one shift to the start of the next, and any that falls under eleven hours is marked on the row, on the grid and in the PDF.
Which means a night shift has to be counted on the day it ends
A shift from 22:00 to 06:00 is written on Monday and finishes on Tuesday. If the arithmetic measures from the day the shift is written on, a Tuesday evening start looks like a twenty two hour gap when it is actually fourteen. That is why the calculation here runs in absolute minutes from the start of the week rather than per day: a shift ending at 02:00 on Saturday ends on Saturday, and everything after it is measured from there.
It is a small piece of arithmetic and it is the reason most rota tools show a night pattern as fine when it is not.
Weekly rest is one block, not a total
Regulation 11 gives twenty four uninterrupted hours in each seven days. The word doing the work is uninterrupted. Six days on with twelve hours off every night adds up to seventy two hours of rest and fails the test, because no single one of those blocks reaches twenty four hours.
An employer may instead give two periods of twenty four hours, or one period of forty eight, in each fourteen days. If that is how you run it, tick the fortnight option and the tool tells you to check this week against the next one rather than judging it alone.
What the 48 hour limit is
It is an average over seventeen weeks, not a cap on any single week, so one heavy week is not a breach by itself. It becomes one when the average goes over, and a signed individual opt-out removes the limit for that person entirely.
What an opt-out does not remove is the rest entitlements. Daily rest, weekly rest and the in-shift break are not opt-outable, which is worth knowing because the opt-out is often signed in the belief that it settles everything about hours. It settles one thing.
Sending it without an account
The rota travels in the fragment of the link, the part after the hash. A fragment is never transmitted to a server in an HTTP request, which is a property of how browsers work rather than a promise we are making, so the rota you build genuinely does not reach us. Anybody you send the link to opens the rota exactly as you built it, with no account and no per-user fee.
The limit is length. The whole rota is in the address, so a very large one runs past what browsers handle reliably, at roughly two thousand characters. When that happens the tool says so and the PDF is the thing to send instead.
Two related tools do the parts this one deliberately does not. The rota cost and wage checker takes the same hours and works out what the week costs including employer on-costs, and flags anybody pushed under the minimum wage by time nobody wrote down. The 48 hour check works the seventeen week average out properly rather than looking at one week. This one answers a narrower question: is the week you have built legal to work.
Common questions
How many hours must there be between two shifts?
Eleven. Regulation 10 of the Working Time Regulations 1998 gives an adult worker eleven consecutive hours of rest in each twenty four hour period. It is the rule a rota grid hides, because the breach does not live in either shift: it lives in the space between them. A Friday finishing at 22:00 followed by a Saturday starting at 06:00 is two ordinary eight hour shifts and an eight hour gap, and it is the pattern this tool exists to catch.
Does a day off count as the weekly rest?
Only if it is genuinely twenty four uninterrupted hours. Regulation 11 gives twenty four uninterrupted hours in each seven days, and it is one continuous period rather than a total. Six days on with twelve hours off each night adds up to seventy two hours of rest and still fails, because none of those blocks is twenty four hours long. An employer may instead give two periods of twenty four hours, or one of forty eight, in each fourteen days.
Why does the tool count a night shift on the following day?
Because that is when it ends, and the gap is measured from the end. A shift from 22:00 to 06:00 finishes the next morning, so the rest before the next shift has to be counted from six in the morning and not from ten the night before. Getting that wrong is why most rota tools show a night pattern as compliant when it is not: they measure from the day the shift is written on rather than from the moment it actually finished.
Is 48 hours a hard weekly limit?
No, it is an average over seventeen weeks rather than a cap on any one week, so a single heavy week is not a breach on its own. It becomes one when the average goes over. A worker can also sign an individual opt-out, which removes the limit for them but not the rest entitlements, which cannot be opted out of. The 48 hour tool on this site works the average out properly across a reference period.
When is a rest break due during a shift?
Where daily working time is more than six hours. Regulation 12 gives an uninterrupted twenty minute break, taken during the working day rather than at the start or the end of it, so sending somebody home twenty minutes early does not satisfy it. Putting the break into the rota rather than leaving it to be taken is also what makes it provable afterwards.
How do I send the rota to the team?
Copy the link. The whole rota is encoded in the part of the address after the hash, and a fragment is never transmitted to a server by the browser, so the rota does not reach us and nobody needs an account to open it. Anyone you send it to gets the rota exactly as you built it and can edit their own copy. There is a size limit, because the rota travels in the address itself, and past roughly two thousand characters browsers stop being reliable. A large rota goes as the PDF instead.
Are there different rules for under 18s?
Yes, and stronger ones. Young workers have their own daily and weekly limits and their own rest entitlements, and unlike the adult 48 hour limit those cannot be opted out of. This tool checks the adult rules only. Some sectors also have their own regimes that displace the general regulations, transport being the obvious one.
Does this work out what the rota costs?
No, that is a separate tool. The rota cost and wage checker on this site takes the hours and the rates and works out the real cost including employer on-costs, and flags anybody pushed under the minimum wage by time nobody wrote down. This one is about whether the week is legal to work, not what it costs to run.