Pay Check Calculator UK
A pay check calculator should answer the payslip question directly: if this is my gross pay for the period, what might I actually take home after tax, National Insurance and pension? This page does that for common UK pay frequencies.
It is useful for checking a new rate, testing a shift in pay, or understanding how a weekly or monthly gross amount might translate into banked pay.
Estimate net pay for a pay period
Enter gross pay for the period, choose weekly, fortnightly or monthly, then add any employee pension contribution rate.
Pay check estimate
How this calculator works
The tool annualises the pay-period gross figure based on the frequency you choose, applies current UK tax and employee National Insurance assumptions, deducts pension and then converts the result back into a single payslip estimate.
That gives a more useful answer than trying to tax one isolated pay period without context.
Worked example
If your monthly gross is £3,200 and you contribute 5% to pension, the calculator first converts that to an annual salary. It then estimates the annual tax and NI burden and divides it back into monthly net pay.
The same logic works for weekly and fortnightly pay too.
2025/26 rates, thresholds, and inputs
The result is designed as a payslip estimate rather than a payroll-engine replica.
| Input | Effect on the result |
|---|---|
| Gross pay | Base amount for the payslip estimate |
| Frequency | Annualises the gross pay correctly |
| Pension rate | Reduces take-home and taxable pay |
| Tax and NI | Applied using current UK rules |
Edge cases and assumptions
- Scottish income tax, student loans and salary sacrifice are not modelled here.
- Large one-off bonuses can make actual payroll behave differently from the smooth annualised estimate.
- Emergency tax codes and cumulative adjustments can also shift the live payslip.
- The pension input is treated as a simple percentage contribution.
FAQs
Is this a gross-to-net payslip calculator?
Yes. It estimates what a weekly, fortnightly or monthly gross pay amount might look like after tax, NI and pension.
Why annualise the gross figure first?
Because UK payroll logic is usually based on annual thresholds and cumulative treatment.
Can I use this for salary sacrifice or student loan?
Not directly. This version is kept deliberately simple for common payslip checks.
Sources and methodology
This tool annualises gross pay by frequency, applies current UK tax and employee NI assumptions, then rebuilds the single payslip estimate.
It is designed for clarity and speed, not for reproducing every payroll edge case.