Tools to explain
how the system works.
This site is built to help UK residents understand their taxes, take-home pay, and savings growth. It is designed for people who want clarity before making decisions or speaking to advisers. We provide accurate calculation tools and clear explanations, not personal financial advice.
Why we built this
We built this site out of frustration with opaque, ad-heavy calculators that often give conflicting results. Many tools hide their workings or fail to explain why a number is what it is. We view personal finance as an engineering problem: the rules are defined by HMRC and the government, and the software should reflect those rules with precision. Our goal is simply to "show the maths" clearly.
Who is behind it
I am a software engineer based in the UK, specializing in building reliable web systems. I am not a financial adviser, and I do not sell financial products. My background is in technology, where accuracy and testing are paramount. I approach these calculators with the same rigour I apply to enterprise software—ensuring the logic holds up against the official rules.
How our calculators work
We rely on primary sources and explicit logic, not estimates or "rules of thumb" unless stated.
- Tax Year: All calculators currently use 2024/25 tax thresholds.
- Sources: Rates are pulled directly from HMRC and GOV.UK documentation.
- Calculations: We calculate National Insurance on a per-pay-period basis (as employers do), rather than a simple annual percentage, to ensure accuracy.
- Limitations: We clearly state assumptions (e.g., standard tax codes like 1257L) and highlight where complex individual circumstances might differ.
Accuracy and Updates
Financial rules change. We commit to updating our tools:
- Immediately following major fiscal events (e.g., Autumn Budget, Spring Budget).
- At the start of each new tax year (April 6th).
- Whenever HMRC publishes new guidance or corrections.
Most calculators will display a "Last Updated" or "Tax Year" badge to confirm they are current.
Important Boundaries
- ✕We do not provide personalised financial advice.
- ✕We do not replace the need for professional, regulated advisers.
- ✕We cannot see your bank account or personal tax account.
Transparency & Business Model
This site is independent. To keep the servers running, we may in the future introduce relevant affiliate links or non-intrusive advertising.
Our promise: Commercial relationships will never influence the output of a calculation. The maths is objective and non-negotiable. Raising revenue is secondary to providing accurate tools.
Primary Sources
We verify our data against:
Corrections & Contact
Accuracy is our priority. If you spot an error or an out-of-date figure, please let us know immediately so we can fix it.