UK calculators
Accurate, interactive calculators built for the United Kingdom — pounds, UK rules and statutory figures like the 5.6-week holiday entitlement and the 10% overpayment allowance. Every tool shows its formula and cites its sources. More are added regularly.
Finance & mortgage
- Stamp duty calculator
SDLT, LBTT and LTT on one page — England & NI, Scotland and Wales compared side by side, with first-time buyer relief, the additional-property surcharges and the non-resident 2%.
- Zakat calculator
Zakat at 2.5% on your zakatable wealth, checked against both the gold and silver nisab (dated UK charity values, editable), with deductible debts handled correctly.
- Annuity calculator
Estimate the yearly income a pension pot could buy, from dated UK benchmark rates by age and product type — with the 25% tax-free lump sum and a level vs escalating breakeven.
- Mortgage overpayment calculator
Interest saved and years knocked off your term from regular and one-off overpayments, with a 10% allowance check and a balance chart.
- Buy-to-let mortgage calculator
Maximum borrowing from the ICR stress test, interest-only vs repayment, gross and net rental yield, the 5% stamp duty surcharge and cash-on-cash ROI — all in one.
- Rent affordability calculator
How much rent you can afford — letting-agent income multiples, the 30% benchmark and the income needed for a target rent.
- Rental yield calculator
Gross and net rental yield with every expense itemized, plus cash-on-cash return if you're buying with a mortgage.
- Land registry fee calculator
Exact HM Land Registry fee from the official Scale 1 and Scale 2 bands, portal vs postal.
- Probate fees calculator
Official probate application fees for England & Wales, Scotland confirmation and Northern Ireland, with the DIY vs solicitor cost comparison.
- Conveyancing fees calculator
Itemized legal fees and disbursements for buying, selling or remortgaging, with leasehold and new-build supplements.
- Estate agent fees calculator
Commission, VAT and net proceeds — high-street percentage versus online fixed fees, side by side.
Salary & tax
- Child maintenance calculator
The statutory CMS formula (April 2026) with every step shown — rate band, other children in your household, shared-care nights compared side by side, and the £3,000/week cap.
- Pro rata calculator
Full-time salary to pro-rata pay by hours or days — annual, monthly, weekly, hourly and daily — plus pro-rata holiday and term-time support.
- Annual leave calculator
UK statutory holiday entitlement (5.6 weeks, 28-day cap) in days and hours, pro-rata for part-time and part-year, plus the 12.07% irregular-hours method. AU page covers the NES 4-week accrual.
- Dividend tax calculator
Your UK dividend tax for 2026/27 band by band, the £500 allowance, your effective rate, and how much extra the April 2026 rate rise costs vs 2025/26.
- Take-home pay calculator
2026/27 UK net pay from salary or hourly rate: rUK vs Scottish tax bands, National Insurance, student loans, pension salary sacrifice and the £100k Personal Allowance taper.
- Hourly wage calculator
Hourly rate to annual, monthly and weekly salary (and back), checked against the April 2026 National Living Wage and Real Living Wage, with an optional 2026/27 take-home estimate.
- Car tax calculator
UK VED for 2026/27 — first-year rate by CO2, standard rate and the expensive-car supplement, EVs included.
- Self-employed tax calculator
Income tax and Class 4 National Insurance on your profits for 2026/27, with payments on account explained.
- Maternity pay calculator
Statutory Maternity Pay week by week — 90 percent for 6 weeks then the 2026/27 flat rate, with eligibility checks.
- Redundancy calculator
Statutory redundancy pay from your age, service and weekly pay, with the 2026/27 caps applied year by year.
Math & numbers
- Volume calculator
Volume of cubes, prisms, cylinders, spheres, cones, pyramids and capsules in metric or imperial units.
- Margin calculator
Gross margin, markup and the difference between them — solve for price, cost or margin in any direction.
- UCAS points calculator
Official UCAS Tariff points for A-levels, BTECs, T-levels, Scottish Highers and IB.
- Trigonometry calculator
Solves right triangles from any two known values with SOH-CAH-TOA steps, degrees and radians, and exact unit-circle values for the special angles.
- University grade calculator
Credit-weighted module averages, year weightings and UK degree classification (First, 2:1, 2:2, Third) — plus the mark you need on remaining credits.
Health & fitness
- Height calculator
Predict a child's adult height as an honest range from both parents' heights (Tanner mid-parental method, ±8.5 cm), plus an exact ft/in ↔ cm converter.
- Dog age calculator
Human-age equivalent using the 2020 epigenetic formula and size-adjusted veterinary tables, versus the old times-7 rule.
- Protein calculator
Daily protein needs in g/kg by goal and activity level, in kg, pounds or stones.
- Period calculator
Next-period and estimated fertile-window dates from your cycle length — a date tool, not a contraceptive method.
Home & trade
- Square meter calculator
Room-by-room floor area in m² from any mix of mm, cm, m, feet and inches — with wastage, packs-needed rounding, cost per m² and exact m²-to-sq-ft conversions.
- BTU calculator
Radiator size for any room as an honest BTU range — room type, glazing, walls and aspect — with watts, the Delta-T50 rule for reading radiator listings, and when you need a proper heat-loss survey.
- Fuel cost calculator
Journey and annual fuel costs from distance, MPG and pence per litre, with return trips, cost per passenger and a petrol vs diesel vs EV comparison.
Date & time
Coming soon.
Everyday & sizing
- Shoe size converter
US, UK, EU and CM (Mondopoint) shoe sizes for men, women and kids, including youth-to-women conversion.
- Bra size calculator
Band and bust measurements to US and UK bra sizes, with sister sizes and the UK cup divergence beyond D explained.
- Typing test
15 to 120-second typing test on real sentences: gross and net WPM, accuracy and a consistency score, using the standard 5-character word.
- Air fryer conversion
Convert oven temperatures and times to air fryer settings — conventional and fan ovens handled separately — with a per-food UK reference table.