Free UK Business &
Finance Calculators
Instant, accurate calculators for UK businesses, freelancers, and homeowners. No signup. Always free.
Browse all 31 free calculators →Browse by Category
Most Popular Tools
View all →Profit Margin Calculator
Work out your profit margin in seconds. Enter your revenue and your item cost (cost of goods sold) to see gross margin, net margin, and markup — each shown as a percentage of revenue. A free margin calculator UK small businesses, freelancers, and online sellers use to price products and keep a clear read on their financial health.
PopularUK VAT Calculator — Add or Remove VAT
Free online VAT calculator for UK businesses and individuals. Add VAT to any net amount or remove VAT from a gross amount instantly. Supports all UK VAT rates — standard 20%, reduced 5%, and zero rate. Use the reverse VAT calculator uk to find the net amount from a gross price, or work out the VAT portion on any products and services. Essential for completing your VAT return, checking invoices, or calculating the gross amount VAT-inclusive on a quote.
PopularIncome Tax Calculator UK 2026/27 — Take Home Pay
On a £35,000 salary in 2026/27 you pay around £4,486 in income tax and £1,790 in National Insurance, leaving take-home pay of about £28,720 a year — roughly £2,393 a month. This free calculator shows that breakdown instantly for any salary, whether you are employed (PAYE) or self-employed. Enter your gross salary to see exactly how much tax and other deductions come off — income tax, National Insurance, student loan, and pension — all against current 2026/27 rates and bands. Use it to see what 45k, 65k, or 90k really means in your pocket, model a pay rise, or compare salaries before you negotiate.
PopularFreelancer Day Rate Calculator
Find out exactly what day rate and hourly rate to charge as a UK freelancer based on your desired annual income, tax, and expenses. Works as a freelance salary calculator too — reverse-calculate the salary equivalent of any day rate.
PopularUK Stamp Duty Calculator 2026/27 — SDLT Land Tax
On a £300,000 home, a standard buyer pays £5,000 in stamp duty (SDLT) — but a first-time buyer pays £0, and a buyer purchasing an additional property pays £20,000. This free calculator works out exactly how much stamp duty land tax you'll pay on any English or Northern Irish property purchase in 2026/27, applying the current band rates automatically based on your purchase price and buyer type (standard, first-time buyer, second home, or buy-to-let). Stamp duty is charged in bands — like income tax — so you only pay each rate on the portion of the price within that band, not on the whole amount. Enter your purchase price below to see your exact SDLT bill before you make an offer.
PopularUK Mortgage Affordability Calculator — How Much Can I Borrow?
Free mortgage calculator UK — use this calculator to work out how much you can borrow based on your salary and deposit. This mortgage affordability calculator uk uses the standard 4–4.5x income multiple UK mortgage lenders apply. Includes a mortgage repayment calculator for regular monthly payment estimates, interest only mortgage comparison, overpayment of mortgage calculator to model overpayments and remaining term reductions, and life insurance cost guidance. Also works as a mortgage calculator how much can i borrow tool for joint applications.
PopularMortgage Overpayment Calculator UK — See How Much You Save
Free mortgage overpayment calculator UK — enter your mortgage balance, interest rate, remaining term, and monthly overpayment to see exactly how much interest you save and how many years you knock off your mortgage. Supports both monthly overpayments and one-off lump sum payments. Includes an overpayment comparison table so you can instantly compare the savings from £100, £200, or £500 extra per month. Most UK lenders allow up to 10% of the outstanding balance overpaid each year without an early repayment charge — this calculator helps you model that benefit.
PopularRental Yield Calculator
Free rental yield calculator for UK landlords and property investors. Calculate gross and net yield — including net initial yield — on any buy-to-let property. Works as a property yield calculator, a property investment calculator, and a buy to let calculator for comparing returns across properties. Enter your property value, monthly rent, mortgage payments, and annual costs to see cash flow and overall return. Essential for long term buy to let investments due diligence.
PopularPay Rise Calculator UK 2026/27 — Take-Home Pay After a Raise
Free UK pay rise calculator that shows exactly how much of a pay increase you actually keep after income tax and National Insurance. Enter your current salary and a pay rise as a percentage or a fixed £ amount to see your new salary, the change in take-home pay (annual and monthly), and the percentage of your raise that goes to tax and NI. Works as a salary increase calculator, an income increase calculator, and a raise in salary calculator — all using up-to-date 2026/27 UK tax bands.
PopularUK BMI Calculator — BMI Checker (NHS Categories)
Free BMI calculator for UK adults. Calculate your body mass index (BMI) and check whether you are a healthy weight. Enter your height and weight, and your BMI result appears in seconds, along with your NHS weight category and the healthy weight range for your height. Body mass index (BMI) is a useful long term guide to your overall health, but it is only one piece of the picture. It does not measure body fat or body composition directly, so muscle mass, age, and body shape all affect what your BMI result really means.
PopularSleep Calculator UK — Best Bedtime & Wake Up Times
Find the best times to wake up or fall asleep based on 90-minute sleep cycles, so you wake feeling refreshed instead of groggy. Enter your alarm time and this sleep cycle calculator counts back through complete cycles to show your ideal bedtimes — or work forwards from your bedtime to find the best wake-up times.
Popular💷 Finance Calculators
All finance →Profit Margin Calculator
PopularUK VAT Calculator — Add or Remove VAT
PopularIncome Tax Calculator UK 2026/27 — Take Home Pay
PopularFreelancer Day Rate Calculator
PopularBreak-Even Calculator
Markup Calculator
ROI Calculator
UK Savings Goal Calculator — ISA & Compound Interest
Salary to Hourly Calculator UK 2026/27 — Convert Any Salary Instantly
Dividend Tax Calculator
Discount Calculator
Salary Sacrifice Calculator
Pro Rata Salary Calculator UK — Part-Time & Holiday Pay
Pay Rise Calculator UK 2026/27 — Take-Home Pay After a Raise
PopularSalary Sacrifice Car Calculator UK 2026/27
🏠 Property Calculators
All property →UK Stamp Duty Calculator 2026/27 — SDLT Land Tax
PopularWales Land Transaction Tax Calculator 2026 — LTT
UK Mortgage Affordability Calculator — How Much Can I Borrow?
PopularMortgage Overpayment Calculator UK — See How Much You Save
PopularRent Affordability Calculator
Rental Yield Calculator
Popular📊 Business Calculators
All business →❤️ Health Calculators
All health →UK BMI Calculator — BMI Checker (NHS Categories)
PopularSleep Calculator UK — Best Bedtime & Wake Up Times
PopularUK Calorie Calculator — TDEE & Daily Calories
TDEE Calculator — Total Daily Energy Expenditure
How Much Water to Drink a Day Calculator — UK Water Intake Tool
Blood Pressure Checker — NHS Blood Pressure Chart UK
Child Growth Chart Calculator UK — NHS Centile Chart
Why Use CalcKit?
Built specifically for UK businesses and individuals. All calculators use current 2025/26 rates and are updated regularly. Learn more about CalcKit →
Free UK Calculators for Every Situation
CalcKit provides free, instant online calculators built specifically for the UK. Whether you are a sole trader working out your take-home pay, a landlord calculating rental yield on a buy-to-let, a small business owner checking your break-even point, or a first-time buyer estimating stamp duty — there is a calculator here for you.
Every financial calculator uses the current 2025/26 HMRC rates and thresholds, including the £12,570 personal allowance, income tax bands at 20%, 40%, and 45%, and National Insurance at 8% up to £50,270 and 2% above. VAT calculators cover all three UK rates: standard 20%, reduced 5%, and zero rate. Stamp duty figures reflect the April 2025 rate changes.
All calculations happen instantly in your browser. No data is ever sent to our servers, no account is required, and there are no hidden fees. We update all rates at the start of each UK tax year so you always get accurate results. Browse all 31 free calculators →
UK Tax & Finance — Key 2025/26 Rates
Who Are These Calculators For?
Sole Traders & Freelancers
Calculate your take-home pay after income tax and Class 4 National Insurance. Work out a day rate that covers your tax bill, holiday pay, and expenses. Check your IR35 status and its financial impact.
Small Business Owners
Find your break-even point, calculate profit margins, add VAT to invoices, and measure ROI before committing to any spend.
Homebuyers & Landlords
Estimate stamp duty before you make an offer, check your mortgage affordability, and calculate rental yield on buy-to-let investments.
Health & Wellbeing
Check your BMI using NHS classifications, find your daily calorie needs, optimise your sleep schedule, and track your water intake.
Latest Guides & Articles
All articles →Contractor vs Employee UK 2026/27: What You Actually Take Home
Contractors typically earn 20–30% more than equivalent employees — but only if you clear the real break-even, which most articles underestimate. Here are the actual numbers.
UK Pension Contributions 2026/27: How Much Should You Pay In?
The auto-enrolment minimum of 8% gets you into a pension, but for most people it won't be enough. Here is how pension contributions work in the UK in 2026/27 — the minimum rates, the qualifying earnings calculation, how tax relief actually saves you money, and what you need to contribute to retire on target.
Child Growth Chart UK: NHS Centiles, Height & Weight by Age
UK child growth charts use nine centile lines, not a single 'ideal' target. A child on the 9th centile can be just as healthy as one on the 91st — what matters is whether they stay consistent. Here is how to read the charts, what the averages are by age, and when to speak to your health visitor or GP.