Unit Converter & Calculator
Convert between 101 units across 19 categories. Instant results with formulas, tables, and expert explanations.
Browse by category
19 categories, 229 pairs.
Weight & Mass
Convert between kilograms, pounds, ounces, stones, tonnes, and more.
Length
Convert between metric and imperial length units: meters, feet, inches, miles, and more.
Volume
Convert between liters, gallons, cubic meters, fluid ounces, and more.
Temperature
Convert between Celsius, Fahrenheit, and Kelvin.
Pressure
Convert between pascal, bar, psi, atmosphere, torr, and more.
Data Storage
Convert between bits, bytes, kilobytes, megabytes, gigabytes, and binary units.
Data Transfer Rate
Convert between bits per second, Mbps, Gbps, and megabytes per second.
Energy
Convert between joules, kilowatt-hours, BTU, calories, and more.
Speed
Convert between mph, km/h, m/s, knots, and more.
Power
Convert between watts, kilowatts, horsepower, BTU/hour, and more.
Time
Convert between seconds, minutes, hours, days, weeks, months, and years.
Area
Convert between square meters, square feet, acres, hectares, and more.
Frequency
Convert between hertz, kilohertz, megahertz, and gigahertz.
Voltage
Convert between volts, millivolts, and kilovolts.
Force
Convert between newtons, pound-force, kilogram-force, and more.
Torque
Convert between newton-meters, foot-pounds, inch-pounds, and kilogram-force meters.
Angle
Convert between degrees, radians, gradians, arc minutes, and arc seconds.
Typography
Convert between pixels, points, ems, and rems for web and print typography.
Fuel Consumption
Convert between MPG, L/100 km, and km/L for fuel-economy comparison.
Built for clarity and confidence
Accurate formulas
Every conversion uses exact constants or NIST-verified factors. Ambiguities like US vs imperial gallon are clearly flagged.
Practical explanations
Not just results — formulas, worked examples, and reference tables so you understand the answer.
Professional UX
Mobile-first design, keyboard accessible, fast loading, and free of clutter.
More than a unit converter
Practical calculators
Solve real-world engineering, construction, and electrical problems.
Concrete Volume
ConstructionCalculate slab, beam, and column concrete volume in cubic yards or cubic meters.
Ohm's Law
ElectricalCalculate voltage, current, resistance, and power using Ohm's law (V = IR).
Voltage Drop
ElectricalCalculate wire voltage drop for any conductor length, gauge, and load.
Horsepower ↔ kW
EngineeringConvert between mechanical horsepower and kilowatts for engines and motors.
BMI Calculator
HealthCalculate Body Mass Index from height and weight in metric or imperial units.
Flow Rate
EngineeringCalculate volumetric or mass flow rate for pipes and ducts.
Reference guides
All guides →SI vs Imperial Units
A clear guide to the metric and imperial systems, where they differ, and which countries use which.
Mass vs Force
Why kg ≠ kgf, and how to avoid the most common unit confusion in engineering.
US vs Imperial Gallon
A US gallon and an imperial gallon are not the same — here's the difference.
Common Pressure Units
psi, bar, pascal, atm — which to use and when. Gauge vs absolute explained.
Temperature Conversion Explained
Celsius, Fahrenheit, and Kelvin formulas with worked examples.
Torque Units Explained
N·m vs ft·lb vs in·lb — torque unit conversions for mechanics and engineers.
Tonne vs Ton: Which Is Which?
Metric tonne, short ton, long ton — the 10% difference that causes real trade disputes.
Binary vs Decimal Data Units
Why 1 GB ≠ 1 GiB, and how storage vendors and operating systems measure capacity differently.
Reference tables
Quick-access conversion tables for length, weight, temperature, pressure, data sizes, and SI prefixes — no inputs needed.
UnitFormula is a technical calculator platform covering unit conversion, engineering calculations, construction tools, and electrical references. Every result includes the formula, a worked example, and a reference table — so you understand the answer, not just the number. All conversion factors are derived from NIST and SI standards. Ambiguous units (US vs imperial gallon, tonne vs short ton, gauge vs absolute pressure) are explicitly flagged.