About CalcStack
CalcStack is a collection of 85+ free UK calculators and tools covering tax, salary, property, business, employment, health and more. Every tool is designed specifically for the United Kingdom — using current UK tax rates, regulations and data sources.
Who it's for
CalcStack is built for anyone who needs quick, accurate UK-specific calculations:
- Professionals — accountants, solicitors, contractors and consultants.
- Homeowners and buyers — stamp duty, mortgage, shared ownership and renovation calculators.
- Business owners — VAT, business rates, dividend tax and startup cost tools.
- Contractors and trades — CIS, day rate, IR35 and scaffolding cost calculators.
- Students and graduates — student loan repayment, graduate salary and childcare cost tools.
Who built it
CalcStack is built and maintained by Flavoureak UK Ltd, a company registered in England and Wales (Company No. 15922329), founded by Jeff Barry and based in Wales. Flavoureak also builds other software products for the UK construction and professional services industries.
Our approach
- Free tools that actually work — no sign-up walls on free calculators. Get your answer instantly.
- No dark patterns — we show you the price upfront. No hidden fees, no bait-and-switch.
- Fair pricing for premium features — premium tools start from just £1.99. Pay once, get your result.
- UK-first — every tool uses current UK tax rates, legal thresholds and data sources. Built by people who understand the UK market.
Technology
CalcStack is built with Next.js and hosted on AWS infrastructure in the UK (eu-west-2, London). Premium AI-powered tools use Amazon Bedrock for secure, private AI processing — your data is never sent to third-party AI providers.
Get in touch
Have a question, suggestion, or found a bug? We would love to hear from you.
Email: [email protected]
Website: flavoureak.co.uk