Kalkulix
EN
UK

Calculators that just work.

Online calculators and converters

Free tools for everyday calculations – currency and unit conversion, payment QR codes, electrical engineering and take-home pay. Fast, accurate and no sign-up required.

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Finance

Currency converter with daily ECB rates and QR codes for instant bank transfers.

Currency converterDaily ECB rates for 30+ currencies including GBP, EUR, CZK and PLN.Payment QR codeSEPA (EPC) QR codes for instant bank transfers.Mortgage calculatorMonthly payment, amortisation and bank-rate comparison.How much can I borrow?Mortgage affordability under the UK LTI multiple.
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Energy

Solar panel ROI and other energy-related calculations.

Solar panel payback calculatorPayback period, savings and export tariff for 2026.
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Sports calculators

Accumulator bet ticket calculator and odds converter between decimal, fractional and American formats.

Accumulator bet calculatorMatch odds and stake → total odds, payout and profit.Odds converterDecimal, fractional and American odds plus implied probability.

Units

Convert length, weight, temperature, volume and other physical quantities.

Length converterMetres, kilometres, inches, feet or miles.Weight converterKilograms, grams, pounds, ounces and stones.Temperature converterCelsius, Fahrenheit and Kelvin.Volume converterLitres, millilitres, gallons or cubic metres.Speed converterkm/h, m/s, mph and knots.Area converterSquare metres, ares, hectares or acres.Pressure converterPascals, bar, atmospheres and psi.Energy converterJoules, calories, kWh or BTU.

Text

Count characters, words and sentences, with social media limits included.

Character and word counterCharacters, words, sentences, reading time and social media limits.Text compareSpot the differences between two texts with colour highlighting.

Electrical

Ohm's law, electrical power, cable sizing and other electrical calculations.

Ohm's law calculatorWork out voltage, current and resistance.Electrical power calculatorSingle-phase and three-phase power.kVA to kW converterApparent and real power with power factor.Cable size calculatorSize conductors by current and cable run length.Capacitor calculatorWork out capacitance, charge and stored energy.Resistor calculatorTotal resistance of series and parallel combinations.

Salary & benefits

Take-home pay, sick pay and maternity benefits for 8 European countries.

Take-home pay calculator – UKIncome Tax, National Insurance, student loans and pension.Statutory Sick Pay calculatorSSP under the rules effective 6 April 2026.
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