All Calculators

112 free, expert-reviewed calculators and converters. No signup required.

🏠 Mortgage & Property

Mortgage Repayment Calculator

Monthly payments, total interest and full amortisation schedule.

Stamp Duty Calculator

Transfer tax for UK, Ireland and EU countries.

Rental Yield Calculator

Gross and net yield on buy-to-let properties.

Mortgage Affordability

How much can you borrow? Income multiple, stress test and LTV.

Mortgage Overpayment

See interest and time saved by overpaying monthly or with a lump sum.

Buy vs Rent Calculator

True total cost of buying versus renting over any timeframe.

💰 Finance & Loans

Loan Repayment Calculator

Monthly payments and amortisation for any loan.

Compound Interest Calculator

See how savings grow with daily or monthly compounding.

Savings Goal Calculator

Monthly savings needed to reach your target by a date.

Credit Card Payoff Calculator

Debt-free date and interest savings.

Monthly Budget Planner

Income vs expenses with category breakdown.

How much to tip and split the bill between any number of people.

Net Worth Calculator

Total your assets and liabilities to see your real financial position. Age-based benchmark included.

APY / APR Calculator

Convert between APR (nominal) and APY (effective) at any compounding frequency.

Inflation Calculator

Adjust money for UK CPI, US CPI or Eurozone HICP — see real buying power across years.

🧾 Tax

Add or remove VAT — all 27 EU member states.

Salary After Tax

Take-home pay for UK, Ireland, Germany, France, Spain.

Income Tax (EU)

Income tax estimates for 7 European countries.

Capital Gains Tax

CGT on shares, property and crypto.

Sales Tax Calculator

Add or remove US sales tax with state-by-state combined averages.

Paycheck Calculator

UK PAYE and US federal take-home pay with NI / FICA, pension or 401k.

Council Tax Calculator

Annual UK council tax for any band. Plug in your local authority's band-D rate.

Hourly to Salary Converter

Convert hourly wage to weekly, monthly and annual salary — UK & EU.

Self-Employed Tax (UK)

Income tax, Class 4 NI and Self Assessment for sole traders.

Dividend Tax Calculator (UK)

2026/27 dividend tax with £500 allowance and band breakdown.

Contractor IR35 Take-Home

Inside vs outside IR35 net pay from your day rate.

Overtime Pay Calculator

Time-and-a-half, double time, custom multipliers — UK, US, EU.

Crypto Tax Calculator

UK CGT 2026/27 + US capital gains on crypto, plus staking and mining income.

💹 Investment & Retirement

Investment Return Calculator

ROI, CAGR and portfolio growth projections.

Retirement Goal Tracker

Are you on track? Projected pot vs. pot needed for your target income.

Stock Profit Calculator

Profit/loss on stock trades including fees and CGT.

Pension Pot Calculator

UK pension or US 401k retirement-pot projection with employer match and tax relief.

401(k) Calculator

US 401(k) projection with employer match, salary growth and 2026 IRS limits.

Social Security Calculator

Estimate your US Social Security benefit at 62, Full Retirement Age and 70.

Required Minimum Distribution from IRA / 401(k). SECURE 2.0 age 73 ready.

SIP / Mutual Fund Calculator

Project SIP, lump sum and step-up returns. Future value, gains, total invested.

Crypto Staking Rewards

Project ETH, SOL, ADA, DOT staking rewards with compounding and price scenarios.

⚕️ Health & Fitness

Body Mass Index with WHO health context.

Daily Calorie Calculator

TDEE based on age, weight, height and activity level.

Body Fat Calculator

Estimate body fat % using the US Navy method and BMI-based formula.

Ideal Weight Calculator

Ideal body weight using Hamwi, Devine, Robinson and Miller formulas.

Water Intake Calculator

Daily hydration needs based on weight, activity and climate.

Sleep Calculator

Best bedtime and wake-up times based on sleep cycles.

Pregnancy Due Date Calculator

Estimated due date, current week and trimester from last period.

Nutrition Calculator

Calories, protein, carbs, fat, vitamins and minerals per food item.

Estimate blood alcohol content based on drinks, weight and time.

Ovulation Calculator

Predict your fertile window, ovulation day and next period from your last period and average cycle length.

Calorie Deficit Calculator

Daily calorie target to reach a goal weight. BMR + TDEE, weeks-to-goal projection and macro split.

Macro Calculator

Daily protein, carbs and fat split with cut/maintain/bulk presets and four split styles.

VO2 Max Calculator

Estimate aerobic fitness from Cooper run, 1.5-mile run or resting heart rate, with age-adjusted ratings.

Height Predictor

Predict a child's adult height from parents using the mid-parental formula plus current growth extrapolation.

Period Calculator

Predict your next 6 periods, fertile window and ovulation day from your cycle data.

Running Pace Calculator

Pace, time and distance for 5K, 10K, half-marathon and marathon.

TDEE Calculator

Total Daily Energy Expenditure with BMR + cut/maintain/bulk targets.

Protein Intake Calculator

Daily protein in grams by goal, with per-meal split and food sources.

GLP-1 Weight Loss Calculator

Project weight loss on Wegovy, Ozempic, Mounjaro or Zepbound from clinical trial averages.

Semaglutide & Tirzepatide Dose

mg → units conversion for compounded vials on a U-100 syringe + titration schedule.

💼 Business

Break-Even Analysis

Units and revenue needed to break even.

Profit Margin Calculator

Gross, operating and net margin.

💱 Currency

Currency Converter

Convert between 160+ currencies using ECB reference rates.

🔢 Maths

Scientific Calculator

Full scientific calculator with trig, log, powers and memory.

Graphing Calculator

Plot and visualise mathematical functions interactively.

Fraction Calculator

Add, subtract, multiply and divide fractions with simplification.

Percentage Calculator

Calculate percentages, increases, decreases and percentage of.

Standard Deviation

Population and sample standard deviation with mean and variance.

Algebra Calculator

Solve linear and quadratic equations step-by-step with a specialised on-screen keyboard.

Calculus Integral Calculator

Indefinite and definite integrals step-by-step. Power rule, trig, exponential, log and u-substitution explained.

Calculus Derivative Calculator

Differentiate any function step-by-step. Power, product, quotient, chain, trig, exponential and log rules explained.

Roll 1 to 50 dice simultaneously — d4, d6, d8, d10, d12, d20 and d100. Animated rolls with statistics.

🛠️ Utility

Exact age in years, months and days, total days lived and days until your next birthday.

Calculate your cumulative GPA from multiple subjects using letter grades and credit hours.

Time Zone Converter

Convert any date and time to multiple time zones simultaneously. DST-aware, all IANA zones supported.

Carbon Footprint Calculator

Estimate your annual CO₂ emissions from transport, home energy, diet and lifestyle. Compare to global averages.

Grade Calculator

Weighted course averages and final-exam-needed solver. US letter grade and UK degree class output.

Time Duration Calculator

Duration between two times, plus add and subtract hours, minutes and seconds. Decimal-hours output for timesheets.

Date Difference Calculator

Days, weeks, months and years between two dates. Add or subtract days from a date and get the day of the week.

Square Footage Calculator

Floor or land area for rectangles, triangles, circles and trapezoids. Converts m², ft², yd², acres and hectares.

Concrete Calculator

Volume of concrete needed for slabs, footings, columns and post holes. Cubic metres, cubic yards and bag count.

Tile, Paint & Flooring Calculator

Tiles, litres of paint or boxes of flooring needed for any room — with built-in waste allowance.

Mulch & Topsoil Calculator

Cubic yards / m³ of mulch, topsoil, compost or gravel from area + depth. Bag count + weight.

Roof Pitch Calculator

Pitch ratio (x:12), angle in degrees and rafter length from rise + run.

Dog Age Calculator

Convert dog years to human years using AVMA logarithmic and AAHA size-adjusted scales.

Final Grade Calculator

What score do I need on my final exam to hit my target grade? Works for any weighting.

Solar Panel Payback Calculator

Cost, generation, savings, SEG income, payback and 25-year ROI for residential PV.

Heat Pump vs Gas Boiler

15-year total cost of an air-source heat pump vs gas boiler. Includes BUS grant + CO₂.

🤖 AI Tools

AI Model Cost Calculator

Compare API pricing for 100+ LLMs including GPT-4o, Claude, Gemini and Llama. Calculate exact token costs.

Prompt Cost Calculator

Paste your prompt, choose a model, and instantly see how many tokens it uses and what it costs to send.

AI vs Human ROI Calculator

Compare AI tool costs against human labour. Monthly savings, annual ROI and break-even with live model pricing.

AI Carbon Footprint Calculator

gCO₂e and kWh per LLM prompt by model and grid region. Compare GPT-4o, Claude, Gemini and Llama.

LLM Cost Comparator

Side-by-side per-million-token cost for GPT-5, Claude Opus 4.7, Gemini 3.1 Pro, Llama, DeepSeek.

📐 Metric & Unit Converters

Kilometres to Miles

Convert km to miles instantly.

Miles to Kilometres

Convert miles to km instantly.

Celsius to Fahrenheit

Convert °C to °F with Kelvin reference.

Fahrenheit to Celsius

Convert °F to °C with Kelvin reference.

Kilograms to Pounds

Convert kg to lb and stones & pounds.

Pounds to Kilograms

Convert lb to kg and stones.

Kilograms to Stones

Convert kg to stones and pounds.

Stones to Kilograms

Convert stones and pounds to kg.

Metres to Feet & Inches

Convert metres to feet and inches.

Feet & Inches to Metres

Convert feet and inches to metres.

Inches to Centimetres

Convert inches to cm and mm.

Centimetres to Inches

Convert cm to inches and feet.

Inches to Millimetres

Convert inches to mm and cm.

Millimetres to Inches

Convert mm to inches and cm.

Convert inches to feet and inches.

Convert feet to total inches, cm and metres.

Convert miles per hour to kilometres per hour.

Convert kilometres per hour to miles per hour.

🚗 Motoring

Auto Loan Calculator

Monthly car payment, total interest and amortisation. Trade-in + sales tax.

Lease vs Buy Car Calculator

True total cost of leasing versus financing — residual, money factor, resale.

EV Charging Cost Calculator

Cost per charge, per mile and annual EV running cost vs petrol. Home, public, rapid mix.

Fuel Cost & MPG Calculator

Trip fuel cost, MPG, cost per mile and annual fuel spend for any car.

Convert miles per hour to km per hour for European driving.

Convert km per hour to miles per hour for UK driving.

Kilometres to Miles

Convert km to miles. Useful for European routes and odometers.

Miles to Kilometres

Convert miles to km. Handy for European hire cars and ferry crossings.

⚡ Energy & Sustainability

Solar Panel Payback

Cost, generation, savings, SEG income, payback and 25-year ROI for residential PV.

Heat Pump vs Gas Boiler

15-year total cost of an air-source heat pump vs gas boiler. Includes UK BUS grant + CO₂ savings.

EV Charging Cost

Cost per charge, per mile and annual EV running cost vs petrol. Home, public, rapid mix.

Carbon Footprint

Annual CO₂ from transport, home energy, diet and lifestyle. Compare to global averages.

AI Carbon Footprint

gCO₂e and kWh per LLM prompt by model and grid region. GPT-4o, Claude, Gemini, Llama.

Fuel Cost & MPG

Trip fuel cost, vehicle MPG / L/100km, cost per mile and annual fuel spend.