How to Use the IR35 Calculator
Enter your day rate and typical working days, and select inside or outside IR35 status — the calculator applies the appropriate tax treatment for each scenario (including umbrella fees for inside IR35, or salary-plus-dividend extraction for outside IR35) to show the resulting take-home pay comparison.
The IR35 Calculator applies the correct tax treatment for each status — here's what to enter for an accurate comparison.
Entering rate and working pattern
Enter your day rate and typical number of working days per month or year — the calculator uses this to compute gross contract income before applying the appropriate tax treatment for the selected IR35 status.
Comparing inside vs. outside IR35 directly
Running the calculation for both statuses at the identical day rate shows the direct take-home pay difference between the two, making concrete exactly how much IR35 status affects real income for the same gross contract terms, as covered in the take-home-pay guide.