Unit Converter

How to use it

This converter handles eight kinds of measurement: length, weight, temperature, volume, area, speed, data storage, and time. Pick a category, then enter a number, choose the unit you're converting from and the unit you want, and the result appears as you type — there's no convert button because the math runs instantly in your browser. Most categories convert by multiplying through a common base unit. Length uses meters, weight uses grams, volume uses liters, area uses square meters, speed uses meters per second, data uses bytes, and time uses seconds. Every unit in a category has a fixed factor relative to that base — a mile is defined as exactly 1609.344 meters, for example — so converting from any unit to any other is just two multiplications: value × source factor ÷ target factor. Temperature is the one exception, because Celsius, Fahrenheit, and Kelvin don't share a common zero point; converting between them needs a formula with an offset, not just a multiplication. Each conversion factor here is a defined international standard, not a rounded approximation, so results are exact to the limits of floating-point arithmetic — about 15 significant digits. The number you see on screen is rounded for readability (usually to 4-6 decimal places), but the underlying calculation keeps full precision, which matters if you're chaining several conversions together or copying a result into a spreadsheet. The swap button reverses the current from/to units without retyping the value, useful when you realize you picked the wrong direction. Each category below also gets its own page with unit-specific guidance — for example, why a US gallon and a UK gallon differ, or why file sizes look smaller in Windows than on the box they came in — because the details that matter for weight and the details that matter for data storage are nothing alike.

Frequently asked questions

How accurate are the conversions?

Conversions use standard international factors and are computed at full floating-point precision, then rounded for display. Results are accurate for everyday and most technical use.

Is my data sent anywhere?

All conversions run in your browser — nothing is uploaded. Once the page is loaded it keeps working without sending any data.

Which unit systems are supported?

Both metric and imperial/US units are included across each category, including US customary units for volume.

Can I convert between different categories, like length to weight?

No — length, weight, volume and the other categories measure different physical quantities, so there's no valid conversion factor between them (a meter has no fixed relationship to a kilogram). Each category on this page only converts within itself, between units that measure the same kind of quantity.