Income Tax Calculator (USA / UK)
Estimate how much income tax you owe in the United States or the United Kingdom. Choose your country, enter your annual income, and see the tax due and your effective rate — with the brackets used shown clearly.
USA: US dollars. UK: pounds sterling.
Your result will appear here
Your estimated income tax
Rates are indicative only. Tax rules change — always check the official source (irs.gov for the USA, gov.uk for the UK) or a tax professional before filing.
How to use
- Choose the United States or the United Kingdom.
- Enter your total annual income before tax.
- Click Calculate Tax to see the tax due, your effective rate and your after-tax income.
Frequently asked questions
Which tax brackets does this calculator use?
USA: 2025 federal single-filer brackets (10% to 37%) with the $15,000 standard deduction. UK: 2025-26 rates — 20% basic rate, 40% higher rate and 45% additional rate, with the £12,570 personal allowance (which tapers above £100,000). Rates are indicative and may change.
What is the difference between the effective and marginal rate?
Your marginal rate is the rate on your next dollar or pound of income. Your effective rate is the total tax divided by your total income — it is almost always lower, because lower brackets tax the first part of your income at lower rates.
Does this include state tax or National Insurance?
No. The USA figure is federal income tax only — state tax is separate. The UK figure is income tax only and does not include National Insurance contributions.
Is this a substitute for a tax return?
No. This is an estimate for planning only. Your real bill depends on deductions, credits, allowances and other income. Check irs.gov or gov.uk, or speak to a tax professional.