All UK Tax & Freelance Calculators
24 free tools for freelancers, contractors, and the self-employed — updated for the 2026/27 tax year.
UK tax for the self-employed is more complex than most people expect when they start out. Unlike employees — who have income tax and National Insurance deducted at source via PAYE — sole traders, freelancers, and contractors are responsible for calculating and paying their own tax through Self Assessment. That means understanding not just income tax rates, but also Class 4 National Insurance, payments on account, allowable expenses, and, for contractors, the implications of IR35 and the choice between operating as a sole trader or limited company.
These tools cover the full range of calculations that come up most often for self-employed people in the UK. Every calculator is based on published HMRC rates and is updated each April for the new tax year. All calculations run entirely in your browser — your numbers are never sent anywhere or stored.
Use the search bar or category filter to find the calculator you need. The guides section covers the context behind the numbers — explaining how Self Assessment works, what expenses you can claim, whether to incorporate, and how IR35 affects contractors.
24 tools
- Income Tax Calculator
See your full tax breakdown by band, including the personal allowance taper.
Tax calculators - Take-Home Pay Calculator
Net salary after income tax, National Insurance, pension, and student loan.
Salary & PAYE - National Insurance Calculator
Class 1, 2, and 4 NI — for employees and the self-employed.
NI & self-employment - HMRC Mileage Calculator
Calculate your AMAP claim — 45p/25p for cars, motorcycle, bicycle, passenger supplement.
Self-employment - IR35 Calculator
Inside vs outside IR35 — the real financial difference.
Contractor tools - VAT Calculator
Add or remove VAT at any rate. Includes flat rate scheme calculator.
VAT - Payment on Account Calculator
Work out your January and July Self Assessment advance payments based on last year's tax bill.
NI & self-employment - Self Assessment Estimator
Estimate your Self Assessment tax bill before you file.
NI & self-employment - Dividend Tax Calculator
Tax on dividends stacked correctly above your other income.
Tax calculators - Flat Rate VAT Scheme Calculator
Calculate FRS VAT owed across all 20 sectors and compare with standard VAT accounting.
VAT - Class 4 NI Calculator
Class 4 NI on self-employed profits — 6% between £12,570 and £50,270, then 2% above. Breakdown by band.
NI & self-employment - Day Rate to Salary
Convert a contractor day rate to an equivalent permanent salary.
Contractor tools - Working from Home Calculator (Simplified)
HMRC flat-rate home working allowance: 25–50 hrs/mo = £10, 51–100 = £18, 101+ = £26.
Self-employment - Marriage Allowance Calculator
Check eligibility and calculate your saving — transfer £1,260 of Personal Allowance to your spouse for up to £252/year.
Tax calculators - Trading Allowance Calculator
See if your side-hustle income is covered by the £1,000 trading allowance — or whether actual expenses save more.
Side hustle - Use of Home as Office Calculator
Apportionment method — room fraction × time fraction × running costs. Often gives a larger deduction than flat rates.
Self-employment - Ltd Company vs Sole Trader
Side-by-side tax comparison for the same profit level.
Contractor tools - Property Allowance Calculator
Check whether your rental income is covered by the £1,000 property allowance or if actual expenses are better.
Property & CGT - Class 2 NI Calculator
Check your Class 2 NI position — treated as paid, automatic credits, or voluntary contributions to protect your State Pension.
NI & self-employment - Pension Contribution Calculator
See the true cost of pension contributions with income tax relief applied.
Salary & PAYE - Umbrella vs PAYE
Compare take-home under an umbrella company versus direct PAYE.
Contractor tools - Student Loan Repayment
Plan 1, 2, 4, 5, and Postgraduate — monthly and annual repayments.
Salary & PAYE - Allowable Expenses
Check which self-employed expenses you can deduct from your profits.
NI & self-employment - CIS Deductions Calculator
Construction Industry Scheme deductions at 20% or 30%.
NI & self-employment
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About the 2026/27 tax year
The 2026/27 tax year runs from 6 April 2026 to 5 April 2027. Key rates include: personal allowance £12,570 (frozen since 2021/22); basic rate income tax 20% on £12,571–£50,270; higher rate 40% on £50,271–£125,140; additional rate 45% above £125,140. Class 4 NI for the self-employed: 6% on profits between £12,570 and £50,270, then 2% above. Dividend allowance: £500. Employee Class 1 NI: 8% on earnings between £12,570 and £50,270, then 2% above. VAT registration threshold: £90,000 taxable turnover in any rolling 12-month period. Corporation tax small profits rate: 19% on profits up to £50,000.