Fast unit conversions for everyday, academic, and technical use
How to use TransformUnits
Choose a conversion category, enter a value, and view the converted result instantly. You can also use the site search to jump directly to a specific conversion
Common conversions
Engineering conversions
Sustainability conversions
Popular conversions
Some of the most commonly used conversions on TransformUnits include:
- Miles to kilometres for travel and road distance.
- Metres to feet for construction, room dimensions, and height.
- Celsius to Fahrenheit for weather and cooking.
- Litres to gallons for fuel, drinks, and household volume.
- Kilograms to pounds for shipping, shopping, and body weight.
- Megabytes to gigabytes for storage and file size comparisons.
If you are not sure where to begin, start with a category below or use the search box to find the exact unit conversion you need.
How TransformUnits works
TransformUnits helps you convert measurement values quickly across common and specialist categories, including length, area, volume, mass, time, speed, temperature, pressure, data, energy, and more. Whether you are checking a quick everyday conversion or comparing technical units for work or study, the goal is to give you a clear result with useful context and related conversions on the same page.
The site is built for people who want a simple converter without clutter, but also need enough information to understand the units they are using. Each converter is designed to make unit changes fast to read, easy to verify, and simple to continue into related conversions.
TransformUnits organizes converters by category so you can move from one unit pair to related conversions without starting over. In addition to the result itself, important pages should explain the units involved, show the basic formula, and link to nearby conversions that users often need next.
Why people use this site
People use unit converters for shopping, travel, schoolwork, engineering tasks, fitness tracking, and quick reference during everyday problem-solving. A good converter should not only return a number, but also help users understand what that number means in context.
Guides & articles
In-depth guides on measurement systems, conversion methods, and practical tips.
- Metric vs Imperial: How the World Ended Up With Two Systems
- Temperature Conversion Pitfalls (and the Difference Between a Degree and an Interval)
- How Conversion Factors Are Derived
- Why Your 1 TB Drive Shows 931 GB
- What "kg CO2e" Actually Means
- Pressure Units in Everyday Life: PSI, Bar, and the Gauge/Absolute Mistake That Actually Matters
- The Three Ounces: Why Avoirdupois, Troy and Fluid Ounces Are Not the Same Unit
- Unit Errors That Cost Real Money: Mars Climate Orbiter and the Gimli Glider
- Lux, Lumens, Foot-Candles and Nits: Four Units That Measure Different Things About Light
- Knots, Mach, and Flight Levels: The Units Aviation Never Metricated
- Significant Figures and Rounding: Why a Precise-Looking Number Can Still Be Wrong
- RMSSD vs SDNN: Why Two Standard HRV Metrics Have No Fixed Conversion Between Them
- The Gallon Problem: US Liquid, US Dry, and Imperial
- Grid Carbon Intensity by Country: Why One Number Never Fits All
- The Energy-Unit Zoo: Joules, Calories, BTUs, kWh and Therms
- Short Ton, Long Ton, Tonne: Three Units, One Word "Ton"
- Fuel Economy: MPG, L/100km, and Why the Arithmetic Misleads
- Paper Sizes: A4, Letter, and the Square Root of Two