What is the difference between kB and KiB?

kB is decimal (1 kB = 1000 B); KiB is binary (1 KiB = 1024 B). Storage vendors use decimal, operating systems often report binary, and the gap grows with size — hence "missing" disk space.

How precise are the conversions?

Factors use standard definitions (inch = 25.4 mm exactly, mile = 1.609344 km). For derived categories like speed, the calculation composes exact factors, so precision is limited by your input, not the table.

Why is temperature in its own category?

Because temperature conversion is not multiplication by a factor — it needs offsets (0 °C = 273.15 K). Treating it like a scaled unit is a classic bug, so it gets dedicated handling.

Unit converter — Guide

Convert between 11 categories of units: length, area, volume, weight, speed, time, data storage, power, pressure, angle and temperature.

What it is and when to use it

Convert across 11 unit categories — length, area, volume, weight, speed, time, data storage, power, pressure, angle and temperature — with one interface. The everyday answer to "how many GB is 4.7 GiB", "mph to km/h" and whether that 100 kB JSON is actually big.

Converts across 11 categories of units, including traditional Chinese units such as jin, liang, mu, chi and li.

How to use it

Pick a category
Enter the value and pick the source unit from the dropdown
Copy the converted result — every unit in the category is listed at once

A worked example

Fill in a sample amount to convert

Copy this into the tool, or open Unit converter

Things that trip people up

Time is calculated as 30 days per month and 365 days per year
Data storage uses powers of 1024 (KB = 1024 bytes)
Temperature uses conversion formulas rather than a shared coefficient

Questions people ask

What is the difference between kB and KiB?: kB is decimal (1 kB = 1000 B); KiB is binary (1 KiB = 1024 B). Storage vendors use decimal, operating systems often report binary, and the gap grows with size — hence "missing" disk space.
How precise are the conversions?: Factors use standard definitions (inch = 25.4 mm exactly, mile = 1.609344 km). For derived categories like speed, the calculation composes exact factors, so precision is limited by your input, not the table.
Why is temperature in its own category?: Because temperature conversion is not multiplication by a factor — it needs offsets (0 °C = 273.15 K). Treating it like a scaled unit is a classic bug, so it gets dedicated handling.

Next steps

Open the Unit converter tool

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