Welcome to UnitConversion.io

Welcome to UnitConversion.io. This website was made to be the best unit conversion website on the internet. The way that I hope to achieve this is to make the pages extremely fast and responsive. As you will see below, there are many unit types and an extensive unit list to choose from, which differentiates UnitConversion.io from other similar sites. Our aim is to be a destination for students, professionals, and everyone in between for converting units quickly and in a well presented format. I hope you enjoy the site, and contact me if you have any feedback!

Blog

How to Fix Windows 11 Hibernation Problems by Checking Power Settings, Drivers, and System Files

October 26th, 2026
Fix Windows 11 hibernation first by checking power settings, then drivers, then system files. Hibernate saves your open work to the drive and powers the PC down, which is great when it behaves and annoying when it acts like a sleepy raccoon ... Read more


Essential curl Commands for Beginners

October 24th, 2026
Use curl when you need a fast answer from a URL without opening a browser. It is a command line tool for transferring data, and it has been around since 1998, which explains why it appears in so many docs, scripts, servers, and API guides ... Read more


HTTP 409 Error Code Explained: How to Troubleshoot API Conflicts With Postman, Insomnia, and Chrome DevTools

October 24th, 2026
Treat HTTP 409 as a conflict with the current state of the resource, not as a random server failure. The request may be valid, the user may be authenticated, and the endpoint may be online, yet the server refuses to apply the change because something already exists, changed, or n... Read more


Online Port Scanner: How It Works and When to Use One

October 24th, 2026
Use an online port scanner when you need a quick, outside-in view of which services are reachable from the public internet. It helps confirm whether ports such as 22, 80, 443, 3389, or 8080 are open, filtered, or closed on a server, router, firewall, or public IP address. That ma... Read more



Unit Conversion



mm

=

cm

Unit Types

Length

Convert units of length. Examples of such units are millimeters and meters.

Length Conversion

Area

Convert units of area. Examples of such units are inches squared and acres.

Area Conversion

Mass

Convert units of mass. Examples of such units are ounces and tonne.

Mass Conversion

Volume

Convert units of volume. Examples of such units are tablespoon and gallons.

Volume Conversion

Temperature

Convert units of temperature. Examples of such units are kelvin and rankine.

Temperature Conversion

Time

Convert units of time. Examples of such units are days and months.

Time Conversion

Speed

Convert units of speed. Examples of such units are kilometers per hour and miles per hour.

Speed Conversion

Pressure

Convert units of pressure. Examples of such units are hectopascals and kilopound per square inch.

Pressure Conversion

Digital

Convert units of digital. Examples of such units are megabits and megabytes.

Digital Conversion

Parts Per

Convert units of parts per. Examples of such units are parts-per-million and parts-per-billion.

Parts Per Conversion

Voltage

Convert units of voltage. Examples of such units are millivolts and kilovolts.

Voltage Conversion

Current

Convert units of current. Examples of such units are milliamps and kiloamps.

Current Conversion

Power

Convert units of power. Examples of such units are watts and megawatts.

Power Conversion

Energy

Convert units of energy. Examples of such units are megawatt hours and gigawatt hours.

Energy Conversion

Volume Flow Rate

Convert units of volume flow rate. Examples of such units are millimeters cubed per second and pints per hour.

Volume Flow Rate Conversion

Frequency

Convert units of frequency. Examples of such units are megahertz and revolutions per minute.

Frequency Conversion

Pace

Convert units of pace. Examples of such units are seconds per meter and seconds per foot.

Pace Conversion

Illuminance

Convert units of illuminance. Examples of such units are lux and foot-candles.

Illuminance Conversion

Reactive Power

Convert units of reactive power. Examples of such units are mvar and gvar.

Reactive Power Conversion

Angle

Convert units of angle. Examples of such units are radians and gradians.

Angle Conversion