About TaxEngines

Our mission

Our mission is to make UK tax easier to understand. Tax affects almost every working adult, yet the rules are often explained in language that assumes prior knowledge. We turn those rules into clear calculators and plain-English explanations, so people can see not just a number but how it was reached.

Our vision

We want TaxEngines to become one of the UK's most trusted independent references for tax and personal finance calculations: a place people return to because the figures are dependable, the assumptions are transparent, and the guidance is written for humans rather than specialists.

Who built TaxEngines

TaxEngines was built and is run by Mohi Uddin (LinkedIn), who has spent 15+ years in digital marketing and marketing automation, with a background spanning customer experience, user experience, data analysis, front-end development, and AI-assisted development, used to design, build and maintain production software efficiently.

That background shapes how TaxEngines is built. Years spent inside marketing automation and data platforms mean an instinctive focus on getting the underlying data right before anything gets presented. Years spent on customer and user experience work mean the site is built to be read and understood, not just technically accurate: plain English, clear layout, no hidden assumptions.

TaxEngines exists because working out what you actually pay in tax in the UK, Income Tax, National Insurance, VAT, Council Tax, NHS Pay, shouldn't mean piecing it together from five different places. Every figure is independently researched and verified against primary sources, GOV.UK, HMRC, ONS, or the relevant devolved government, sourced, dated, and cited so you know it's current and where it came from.

This isn't a first attempt at building something people actually use. ImageOptimise.com, a free, privacy-first image tool used by developers and marketers, is another independent project built and maintained the same way: solve one problem simply, without the usual clutter.

TaxEngines is an independent project. There's no advertising influence over the numbers, and nothing here is financial or tax advice, just clear, sourced information so you can make your own decisions.

Why TaxEngines exists

Many online calculators give a single figure with no explanation, no stated tax year, and no indication of what was included or left out. That makes them hard to trust and easy to misuse.

TaxEngines was built to do the opposite. Every calculator states the tax year it uses, shows a full breakdown of the result, and links to the official sources behind the rules. If a figure looks surprising, you can see exactly why.

Who the platform is for

TaxEngines is for anyone who needs a clear, reliable estimate without specialist software or an accountant on hand.

• Employees checking take-home pay, a pay rise or a new job offer.
• Self-employed people and freelancers planning for tax.
• Students and graduates working out student loan repayments.
• Anyone comparing options: pension contributions, salary changes, or working in different parts of the UK.

Our principles

A small set of principles guides everything we publish.

• Transparency: every assumption and tax year is stated openly.
• Accuracy: calculations follow published HMRC rules and are checked against official figures.
• Independence: we are not selling a financial product, and results are not shaped by advertisers.
• Clarity: explanations are written in plain English, not jargon.
• Maintainability: tax data is kept separate from calculation logic, so figures can be updated reliably each year.

Our accuracy commitment

Every calculator is built around published HMRC rates and thresholds for a specific tax year. Tax-year data is stored separately from the calculation logic and the way results are displayed, which keeps updates predictable and reduces the risk of errors creeping in.

Calculations are validated against official figures and covered by automated tests. Where a calculation involves an assumption, for example a standard tax code or a specific National Insurance category, that assumption is stated so you can judge whether it fits your situation.

Annual review process

UK tax rules are set per tax year, which runs from 6 April to 5 April. Ahead of each new tax year we review the rates, thresholds and allowances used by every calculator, update the underlying data, and re-check the results against official sources before publishing.

Each calculator and reference page shows when it was last reviewed and when it is next due for review, so you can see how current the information is.

Supported tax years

The platform currently supports the 2024/25, 2025/26 and 2026/27 tax years, with 2026/27 as the current default. Keeping several recent years available means you can check historical figures as well as the current position.

Our relationship with HMRC

TaxEngines is an independent platform. We are not part of, endorsed by, or affiliated with HM Revenue & Customs or any government department.

We base our calculations on the rates and rules published by HMRC and GOV.UK, and we link to those official sources throughout the site. For anything requiring an official figure, a formal ruling, or action on your tax account, HMRC and GOV.UK remain the authoritative sources.

Our roadmap

TaxEngines started with a single calculator and has grown a great deal since. Rather than repeat a fixed list here that would only go stale again, the All calculators page always reflects exactly what is live today.

• Corporation Tax, for limited companies: not yet covered.
• A growing library of plain-English guides linked to the calculators they support.
• Deeper reference material, including further historical tax-year data and more worked examples.

We would rather release each tool carefully than publish many at once, so the roadmap prioritises accuracy and clarity over breadth.