Enter the date and times of the shift, any unpaid break and your hourly rate, then the premiums your contract pays. The calculator splits the hours between day and night, weekdays, Saturday, Sunday and bank holidays, even when a shift runs past midnight, and shows the basic pay, each premium and the gross total to the penny. It also checks your basic rate against the minimum wage for your age, and your break, and for workers under 18 the length and times of the shift, against the working time rules. It covers England, Wales, Scotland and Northern Ireland. It does not work out overtime, which depends on your weekly hours, or take-home pay after tax and National Insurance.
Enter the shift
The date is the day the shift starts. A finish time earlier than the start means the next day, so 22:00 to 06:00 is an 8-hour shift. Enter any unpaid break in minutes and, if you know it, when it starts. Otherwise it is placed in the middle of the shift, which is where GOV.UK says a rest break should be taken.
Enter your premiums
No UK law gives extra pay for nights, weekends or bank holidays: any premium comes from your contract. Enter each one as a percentage of your hourly rate: time and a quarter is 25, time and a half 50 and double time 100. If your contract pays a fixed amount an hour, divide it by your hourly rate: £1.50 on £12.71 is 11.8%. The night window starts as 11pm to 6am, the legal night period unless you have agreed another, so change it to your contract’s.
How the hours are counted
Every paid minute counts once at your basic rate. A minute in the night window also earns the night premium, and a minute on a Saturday, Sunday or bank holiday earns that day’s premium. The two add up, each worked out on the basic rate. A bank holiday that falls on a weekend gets the higher of the two day premiums. The bank holidays are the ones GOV.UK lists for your nation, substitute days included.
What it checks
Your basic rate is checked against the minimum wage in force on the date of the shift for your age band. From 1 April 2026 that is £12.71 an hour at 21 and over, £10.85 at 18 to 20, and £8.00 under 18 or for apprentices. It also flags a shift of more than 6 hours with a break under 20 minutes. For workers under 18, it flags a break under 30 minutes after 4.5 hours, more than 8 hours in the day, or work between 10pm and 6am.
Basic pay = paid time × hourly rate.
Night premium = night hours × hourly rate × night premium.
Saturday, Sunday or bank holiday premium = hours on that day × hourly rate × that day’s premium.
Gross pay for the shift = basic pay + premiums. Each amount is rounded to the penny; the total is the sum of the rounded amounts.
Example: HMRC’s shift allowance week
In HMRC’s own example, a worker on a basic £12.15 an hour works 10 hours on weekdays and 10 hours at the weekend with a premium of £0.90 an hour, and is paid £252. As four 5-hour shifts, each weekday shift pays 5 × £12.15 = £60.75 and each weekend shift £60.75 plus 5 × £0.90 = £4.50, so £65.25 (enter the premium as 7.41%, which is £0.90 on £12.15). The premium does not count towards the minimum wage, so the minimum wage pay is £243, or £12.15 an hour. That is below the £12.21 National Living Wage of April 2025 to March 2026, and the calculator flags it on each shift.