About CalculateToolbox
Practical money guidance and free calculators for freelancers, the self-employed, and small business owners.
CalculateToolbox started with a simple belief: the people who most need clear financial answers — freelancers, contractors, sole traders, and small business owners — are often the ones with the least time to dig for them. When you are running everything yourself, you do not have an accounts department to ask "what should I charge?" or "how much will I actually take home after tax?"
This site exists to give you those answers in seconds. Every calculator is free, needs no sign-up, stores none of your data, and uses the official current rules — UK tools use the latest HMRC rates for the 2025/26 tax year.
What we are building
CalculateToolbox is growing into a practical resource for small business and self-employed life. Right now that means a set of free, accurate calculators covering the decisions that come up most often:
- Working for yourself: freelance day rate, salary take-home, VAT, and redundancy pay calculators
- Property and borrowing: mortgage, stamp duty, loan, and rental affordability calculators
- Planning ahead: compound interest, percentage, and everyday conversion tools
Over time we are adding more practical sales and small-business guidance alongside the tools — plain-English articles on the things that genuinely help when you are building something on your own.
Who runs this site
CalculateToolbox is an independent site built and maintained in Surrey, United Kingdom, by Nick Brown. Nick has spent more than 35 years in B2B sales and commercial partnerships, working with organisations including Disney, ITV, Eurosport, and FIFA+, and now runs Browny Consulting, helping growing companies learn how to sell what they have built.
That background is why this site leans towards the commercial and self-employed side of life — these are the questions Nick has spent a career helping people answer. CalculateToolbox is a small, self-funded project, built to be genuinely useful rather than to harvest your data.
How we keep it free
This site is supported by advertising. The small ads you may see alongside our calculators let us keep every tool completely free, with no sign-up and no paywall. We never charge for a calculator, and we never sell or share anything you type into one — calculations happen entirely in your browser.
A note on accuracy
We take accuracy seriously and update our tools when rates and rules change. But every calculator here is for guidance only — it is not a substitute for professional financial, legal, tax, or medical advice. For decisions that matter, please consult a qualified professional who can consider your individual circumstances.
Get in touch
We welcome feedback, corrections, and suggestions for new calculators. If you have spotted an error or there is a tool you would like us to build, please visit our Contact page — we read every message.
Last updated: May 2026