All Calculators

How the calculators work, and what they assume

Every calculator on this page runs the same engine: the 2026/27 income tax bands for England, Wales and Northern Ireland or the six Scottish bands, the National Insurance thresholds, the student loan plans and the auto-enrolment pension rules. The order of operations matters and is the same everywhere: salary sacrifice contributions come off first, then income tax on what remains above the personal allowance, then National Insurance, then any student loan repayment.

The default assumptions are the standard ones: a single job, the 1257L tax code, no benefits in kind, no salary sacrifice unless you enter it. Those are the conditions most employees are in, and they are also the conditions under which a calculation matches a payslip exactly. Change any of them and the figure moves, which is why each calculator asks for the inputs it needs rather than guessing.

Nothing you type leaves your browser. There is no account, no saved history and no server-side calculation, which is also why a result disappears when you close the tab. Audience measurement records which page was visited and nothing about the figures entered into it.

Choosing the right tool for the question

For a straightforward salary, the take-home calculator gives the monthly and annual figures with the deductions broken out. For a part-time role, the pro-rata calculator scales the full-time equivalent and applies tax to the lower figure, which is where the personal allowance makes part-time work proportionally cheaper to tax.

For a bonus, use the dedicated tool rather than adding the amount to the annual salary: PAYE treats a bonus month as though it were typical, so the deduction on the payslip is usually larger than the eventual liability, and the bonus calculator shows both. For two jobs, the two-jobs calculator applies the thresholds to each employment separately, which a single-salary calculation cannot do.

For anyone hiring, the employer cost calculator adds National Insurance at 15 per cent above £5,000, the minimum pension contribution and the Employment Allowance where it applies, which together put the true cost of a hire fifteen to twenty per cent above the salary. And for a budget set in net pounds, the required salary calculator works backwards from the take-home you need to the gross to ask for.

The three inputs that change a result most

The tax code is the first. 1257L is the standard code for someone with one job and no benefits in kind; a BR code taxes everything at the basic rate from the first pound, a D0 code at the higher rate, and an emergency code applies the allowance on a non-cumulative basis. A wrong code is the single commonest cause of a payslip that does not match a calculation, and it is corrected by HMRC rather than by the employer.

The pension contribution is the second, and the mechanism matters as much as the amount. Salary sacrifice reduces gross pay, so it cuts income tax and National Insurance together; a net pay arrangement cuts income tax only; relief at source requires a higher-rate taxpayer to claim the extra relief separately, which many never do. The same five per cent produces three different take-home figures.

The student loan plan is the third. Plans 1, 2, 4 and 5 have thresholds differing by thousands of pounds, and a postgraduate loan is repaid alongside an undergraduate one at a further six per cent. Selecting the wrong plan, or forgetting one entirely, can shift the monthly result by more than a hundred pounds.

Reading a payslip against a calculation

Four lines settle almost every discrepancy. The gross for the period should match the salary divided by the number of pay periods, plus any bonus or overtime. The taxable pay should be the gross minus pre-tax deductions, which is the figure the tax is actually charged on. The tax code should be the one HMRC has issued, visible in your personal tax account. And the year-to-date columns should rise consistently from month to month.

Where the calculation and the payslip still differ, the usual culprits in order are a benefit in kind reducing the allowance through the code, a student loan plan not accounted for, a pension deducted after tax rather than before, and a mid-year change of job carrying over figures from a P45. Each of those is visible on the payslip once you know to look for it.

Scotland, and why one line of the payslip differs

Income tax on earnings is devolved to Scotland, which applies six bands from 19 to 48 per cent instead of the three used in the rest of the UK. Below roughly £28,000 a Scottish taxpayer pays slightly less; above that they pay more, and the difference grows with income until it exceeds three thousand pounds a year at the top. Residence decides which schedule applies, not the employer's address, and HMRC marks it with an S prefix on the tax code.

Everything else stays the same. National Insurance, dividend tax, savings interest tax and capital gains tax are reserved and identical across the four nations, which is why only one line of a Scottish payslip differs from an English one. Pension relief follows the Scottish rates, so an intermediate-rate taxpayer is entitled to 21 per cent rather than 20, and the extra point has to be claimed from HMRC rather than arriving automatically through the provider.

What these calculators deliberately do not do

They do not model benefits in kind, because the tax on a company car or private medical cover arrives through the tax code rather than through the payslip arithmetic, and the amounts depend on details only the P11D holds. They do not model the high income child benefit charge, which is settled through self-assessment rather than PAYE. And they do not model mid-year job changes, where a P45 carries year-to-date figures into the new employment and changes the cumulative calculation.

In each of those cases the right tool is your personal tax account on GOV.UK, which holds the actual figures HMRC is working from. The calculators here are for the question they answer well: what a given salary produces in a normal month, and how a change to pay, hours, pension or location moves it.

Keeping a payslip honest over a year

Check the first payslip of a new job, the first after any pay rise, and the first of each tax year in April. Those three moments cover almost every error that PAYE produces, and catching one in month one costs a phone call while catching it in month eleven costs a reconciliation. The figures to compare are the tax code, the taxable pay and the year-to-date columns.

Keep the P60 each May and the P11D each July. Between them they prove a year's income and benefits, which matters for a mortgage application, a tax return and any dispute with HMRC. Three years is the usual retention period for an ordinary return, six where income may have been understated, and there is no limit where a return was never filed at all.

A note on accuracy and on limits

These tools apply published rules to the figures you enter, which makes them exact for the case they model and indicative for a real payslip. The gap between the two comes from details a calculator cannot know: a code adjusted for an earlier underpayment, a benefit in kind, a mid-year change of employer, a salary sacrifice arrangement run outside payroll. None of those is exotic, and each moves the result.

They are also not advice. They will tell you what the rules produce; they will not tell you whether to take a job, sacrifice a bonus or move to Scotland. For a decision with money or a deadline attached, an accountant or the relevant HMRC helpline is the right next step, and arriving at that conversation with the figures already worked out is what makes it short.