Unit Converters

13 free tools · runs in your browser

Weight, height, length, temperature, speed, data, volume and many other unit converters with instant results. Every tool listed here is free and needs no account.

Convert weight, height, length, temperature, speed, data, and volume instantly, with every sibling unit updating live as you type. Includes stone, Rankine, knots, cooking measures, and bytes through terabytes. All factors are exact constants computed locally in your browser.

Weight Converter

kg, lb, oz, stone, grams and tons

Height Converter

Feet/inches to cm and meters

Length Converter

Meters, miles, feet, inches, km and more

Temperature Converter

Celsius, Fahrenheit, Kelvin and Rankine

Speed Converter

km/h, mph, m/s, knots, mach

Data Size Converter

Bytes, KB, MB, GB, TB and bits

Area Converter

Square meters, feet, acres, hectares

Volume Converter

Liters, gallons, cups, milliliters

Cooking Measurement Converter

Cups, tablespoons, teaspoons, ml, grams

Time Unit Converter

Seconds, minutes, hours, days, weeks

Pressure Converter

Pascal, bar, PSI, atmospheres, mmHg

Energy Converter

Joules, calories, kWh, BTU

Angle Converter

Degrees, radians, gradians, turns

Related guides

All guides

unitsFeet and Inches to Centimeters: Height ExplainedA height like 5′10″ is a pair of numbers, not a decimal: five feet plus ten inches, with the feet converting at 30.48 centimeters and the inches at 2.54. The arithmetic, the four mistakes that corrupt height records, and the settings where precision actually matters are below; to convert one height in either direction, the height converter linked from this guide gives the exact pair instantly.6 min read · Read →webdevPX vs REM vs EM: Which Unit Belongs Wherepx ignores the font size a reader has set, rem follows the root element, and em follows the parent, so nesting em compounds while rem never surprises you. That single difference is the whole accessibility case for font-size guidance, and it is what decides where each unit belongs in a layout. The rule of thumb, the arithmetic and the traps are below; to convert one specific value, the PX to REM converter linked from this guide does it instantly.4 min read · Read →CalculatorsBMI: What Body Mass Index Misses and What to Use InsteadBMI tells weight per height squared, not health. Discover its blind spots for athletes, seniors, and different ethnicities, and better metrics to pair it with.6 min read · Read →

In this collection

Every ruler you'll ever need

Thirteen converters span weight, length, height, temperature, speed, area, volume, pressure, energy, angle, time, data storage, and cooking measures. Type into any field and every sibling unit updates live, including the odd ones such as stone, Rankine, knots, and mach that other converters skip. There is no separate convert button — the moment you type, the whole table moves, so you can compare scales at a glance. A change in one field ripples through every related unit instantly. There is no convert button to click, so updating one value immediately reflects across every related unit.

The Cooking Converter deserves special mention for translating between cups, tablespoons, milliliters, and grams in one view, and the Data Storage Converter keeps bytes through terabytes straight when plans and drives disagree. All factors are exact constants, computed locally, so a conversion you make today matches the one you make next month. You can flip between metric and imperial without hunting for a formula, and the result is deterministic every time.

Key tools include the Length Converter for distance, the Temperature Converter for Celsius and Fahrenheit, the Weight Converter for mass, the Cooking Converter for recipe measures, and the Data Storage Converter for bytes and beyond. Each covers a distinct measurement domain so you are not using a length converter for a temperature question, and each updates every sibling unit as you type. The interface stays the same whether you are converting a recipe or a data plan.

Every factor is an exact constant computed in your browser. No conversion leaves your tab, and there is no server involved in looking up a formula. This means the result you get is deterministic and private, whether you are converting a recipe or a data plan, and nothing you enter is retained after you close the tab. A measurement stays between you and your own machine.

Common uses include converting a recipe from cups to grams, checking a speed limit in a different unit, converting storage sizes for a drive, and working out temperature differences between cities. To get started, type a value into any field in the converter and watch every sibling unit update immediately. Every conversion is computed locally, so a measurement never leaves your tab. The related guides link back to two or three tools from this category for worked examples, so you can see a complete conversion before you try your own values.

All 13 of these run client-side in your browser: nothing you paste or drop here is uploaded, and no tool in this category contacts a third-party service. Results are copied or saved straight from the page. For worked examples, the related guides above each link back to 2–3 tools from this category.

All Unit Converters tools (13)