Unit Converter
Length, weight, temperature — convert instantly.
Choose a category, pick the units you want, and type a value to see the result instantly.
Why is unit conversion so easy to get wrong?
Most of the world uses the metric system (meters, kilograms, Celsius), while the US still runs on imperial/US customary units (feet, pounds, Fahrenheit). That mismatch is exactly where mistakes happen — shopping on international sites, following a foreign recipe, or comparing height and weight across countries. This tool has precise conversion ratios built in, so you don't need to memorize or look up formulas.
Common conversion formulas
Temperature is the trickiest one, since Celsius and Fahrenheit aren't a simple multiplication — it's a "multiply then add" linear formula, which is easy to get backwards. It's usually safer to just run the conversion through a tool rather than doing the math by hand.
Frequently asked questions
How do I convert 170cm to feet and inches?
170 cm ≈ 5.58 feet, which is usually written as 5'7" (5 feet 7 inches) in the conventional feet-and-inches format. That notation differs from a plain decimal feet figure, so it's worth double-checking which format a site or document expects.
What's a quick way to understand Celsius vs. Fahrenheit?
0°C (freezing) equals 32°F, and 100°C (boiling) equals 212°F. A comfortable room temperature of 20-25°C works out to roughly 68-77°F — so if a US weather forecast says "around 70°F," that's close to a comfortable, mild day.
What's the easiest mistake to make converting kg and lbs?
Mixing up the direction of the ratio: 1 kg is about 2.2 lbs, not the other way around. Fitness and nutrition sources from the US often use pounds, and converting in the wrong direction throws the number off by more than double — worth double-checking with a tool rather than doing it from memory.
Related Tools
📖 Related guide
Review common conversion mistakes and a simple way to check the direction and reasonableness of a result.
Read the unit guide →How to avoid unit-conversion mistakes
When approximate conversion is enough
Travel, cooking, and shopping usually tolerate small rounding. Engineering, dosing, or legal specifications need authoritative constants and calibrated instruments—not a general web converter alone.
Confirm you selected the correct unit pair before trusting the output. Conversion runs locally in the browser.