Free Online Converters & Unit Tools

Convert Metric, Imperial, & Astronomical units instantly.

Convert numbers to Roman numerals and back instantly.

Convert ratios to percentages, decimals, and fractional parts.

Convert Bytes, KB, MB, GB, TB, PB instantly.

Live exchange rates for all world currencies.

Convert Markdown, HTML, JSON, CSV, and PDF formats.

Convert MP3, WAV, AAC, OGG, FLAC formats instantly.

Convert MP4, WEBM, AVI, MOV, MKV formats instantly.

Convert px, rem, em, %, vw, vh, and CSS units instantly.

Convert dates and times across global time zones.

Convert Text, Base64, ASCII, Hex, Binary, URL instantly.

Convert MPG (US & UK), L/100km, and km/L instantly.

Convert Hz, kHz, MHz, GHz, RPM, and rad/s.

Convert N·m, kgf·m, lbf·ft, and lbf·in.

Convert kg/m³, g/cm³, lb/ft³, and lb/in³.

Convert Dynamic (cP) & Kinematic (cSt) viscosity.

Convert GPM, L/min, m³/s, and cfs.

Convert m/s², g-force, ft/s², and more.

Convert Newton, kgf, lbf, and Dynes.

Convert Joules, N·m, ft·lb, and Wh.

Convert W/m², BTU/h·ft², and W/cm².

Convert Ampere, mA, kA, and µA.

Convert Volts, Millivolts, and Kilovolts.

Convert Ohms, kΩ, MΩ, and mΩ.

Convert Siemens, Mho, mS, and µS.

Convert Farads, µF, nF, and pF.

Convert Henry, mH, µH, and nH.

Convert Nits, Lamberts, and Foot-Lamberts.

Convert Lux, Foot-candles, and Phots.

Convert Gray, Rad, Sievert, and Rem.

Convert Decibels, Bels, and Nepers.

Convert PX, REM, EM, PT, and %.

Convert A4, Letter, Legal to px, mm, inches.

Scale resolutions, calc aspect ratios and pixels.

Convert between DD and DMS coordinates.

Convert Cups, Grams, ml, and Temperatures.

Men, Women, Kids sizes (US, UK, EU, CM).

Tops, Dresses, Pants (US, UK, EU, Int'l).

Convert data between JSON and CSV formats.

Convert between JSON and YAML config formats.

Convert numbers and currency amounts to text.

Convert decimals to simplified fractions.

Convert Acre, Bigha, Guntha, Sq.ft etc.

Convert between Square Meters, Acres, Hectares, and more.

Convert Liters, Gallons, Cups, and more.

Convert Kg, Lbs, Stones, and more.

Convert Celsius, Fahrenheit, and Kelvin.

Convert Seconds, Hours, Years, and more.

Convert MPH, KPH, Knots, and Mach.

Convert Joules, Calories, kWh, and BTU.

Convert Watts, Horsepower, and BTUs.

Convert PSI, Bar, Pascal, and Atmospheres.

Convert Degrees, Radians, and Gradians.

Binary, Hex, Decimal, and Octal.

Percent, Decimal, and Fraction with simplification.

Convert between different units of length, weight, temperature, volume, and area.

Convert between pH and pOH (pH + pOH = 14).

Convert numbers to/from scientific notation.

Visualize time overlap across cities with a meeting planner slider.

Convert Epoch time to Date and vice-versa. Includes live ticker.

Generate ISO 8601, SQL, and US/EU date strings instantly.