Converts an annual salary into an equivalent contractor day rate, or a day rate into an equivalent annual salary, in both directions, with an optional employer on-costs (NI + pension) toggle.
Indicative only. Does not determine inside/outside IR35 status. UK 2025/26 statutory figures.
Does not determine inside/outside IR35 status. See the note above the breakdown. For estimating guidance only; verify against current HMRC figures.
About this day rate to salary converter
This free day rate to salary converter turns an annual salary into an equivalent contractor day rate, or a day rate back into an equivalent salary, in both directions, with an optional employer on-costs (National Insurance and pension) toggle. It is aimed at UK contractors, recruiters, hiring managers and anyone weighing a permanent role against a day-rate engagement, and always shows both the plain and the with-on-costs day rate so you can compare like for like. Everything runs in your browser. Nothing is uploaded.
How the day rate is calculated
Billable days a year are (weeks × days per week) − holiday − other non-billable days, and the plain day rate is salary ÷ billable days (or, in reverse, the day rate itself). The employer on-costs use the UK 2025/26 statutory figures: employer secondary Class 1 National Insurance is max(0, salary − secondary threshold) × 15%, and auto-enrolment pension is max(0, min(salary, upper limit) − lower limit) × 3% across the qualifying-earnings band. The with-on-costs day rate is (salary + employer NI + pension) ÷ billable days. Both day-rate figures are always computed; the on-costs switch only decides which one is the headline. The tool does not determine IR35 status.
Frequently asked questions
Does this tell me if I'm inside or outside IR35?
No. Whether an engagement is inside or outside IR35 changes what a contractor actually keeps, but this tool does not compute or determine it. Use HMRC's free Check Employment Status for Tax (CEST) tool and obtain a formal status determination for a specific engagement.
What holiday figure should I enter?
The UK statutory minimum is 5.6 weeks, 28 days for a five-day week, inclusive of bank holidays. Add any other non-billable time (bench, admin, sales, sickness) separately so the billable-days denominator reflects reality.
Are the NI and pension figures current?
They default to the UK 2025/26 statutory values, 15% employer NI above a £5,000 secondary threshold, and 3% auto-enrolment pension on the £6,240–£50,270 qualifying-earnings band, and every one is editable. Verify against current HMRC figures before relying on the numbers.