About ComputeNow
ComputeNow shows you every line of the sum, then what's left each month. It is an independent website of free UK calculators for pay, tax, property, vehicles, loans and savings.
What we do
There are 40 calculators, from take-home pay and stamp duty to car tax, pensions and import duty. Every one shows its working line by line, says which tax year it uses and when its rates were last checked (currently 18 October 2026), and lists the official sources behind it.
The calculators feed one money plan, What's Left: 7 steps from your take-home pay to your home, car, debts, savings and pension, ending with what is left each month.
Why we built it
Most people meet tax and borrowing rules a few times a year, usually when something changes: a new job, a pay rise, a remortgage, a new car. The rules have changed under them too. The tax-free allowance has been frozen since April 2021 and will stay frozen until April 2031, so pay rises lose more to tax than people expect. And most tools show one number on its own. We wanted one place that is up to date, shows every line, and joins the numbers up.
Where the numbers come from
Every rate and threshold comes from GOV.UK, HMRC, Revenue Scotland, the Welsh Government, the Bank of England, the ONS or the FCA, and is kept with a link to its source. For the 2026/27 tax year, each calculator is tested against worked examples calculated by hand from the published rules. Read how we calculate for the full list of sources and every change we have made.
Why is this free?
ComputeNow is free because it shows ads. Advertisers don't see what you type and have no say in the figures, and we never sell your personal data. There is no sign-up and no bank login. Anything you type into a calculator stays in your browser, and What's Left is saved only on your own device.
Independent, not advice
We are not financial advisers and nothing here is personal advice. For decisions about your own money, speak to a regulated adviser or use the free guidance at MoneyHelper or Citizens Advice. If you are worried about debt, StepChange gives free, confidential advice.
Get in touch
Found a figure that looks wrong, or want a calculator we don't have? Contact us. We read every message.
Guides and help
Our guides
Official services and free advice
These results are an estimate, not financial advice. They use the 2026/27 rates in force on 24 October 2026 and the inputs shown, so your actual tax, pay or costs may differ. Before making a decision about your money, check the figures with HMRC or your provider, or speak to a regulated financial adviser. Free, impartial guidance is available from MoneyHelper.
This page explains the rules using the 2026/27 rates in force on 24 October 2026. It is general information, not financial advice. For decisions about your own money, speak to a regulated financial adviser, or get free, impartial guidance from MoneyHelper.