An exact unit converter with no sign up
Whether you're converting a recipe from metric to imperial, checking a shipping weight in pounds against a kilogram limit, or figuring out what a forecast in Fahrenheit means in Celsius, this tool gives you an instant, exact answer with no account needed. Every calculation happens directly in your browser using standard, precise conversion factors — not rounded approximations.
How it works
- Pick a category. Choose Length, Weight, or Temperature.
- Enter a value and pick units. Select what you're converting from and to.
- Read the result instantly. The converted value updates as you type, with no need to click a button.
Common conversions people look up
- Centimeters to inches, for furniture dimensions or clothing sizes.
- Kilograms to pounds, for body weight, luggage, or shipping limits.
- Celsius to Fahrenheit, for weather forecasts or oven temperatures.
- Miles to kilometers, for travel distances or running routes.
Why the categories are kept separate
Length, weight, and temperature each measure a fundamentally different kind of quantity, so this tool keeps them in separate tabs rather than one long combined list. This also avoids a subtle mistake that's easy to make with temperature specifically: unlike length or weight, converting between Celsius and Fahrenheit isn't just multiplying by a fixed factor — it involves a scale shift too, which is handled correctly here rather than approximated.
Your data stays private
Nothing you enter into this converter is sent anywhere — every calculation happens locally in your browser. See our Privacy Policy for full details.
Quick reference: common conversions
| From | To | Equals |
|---|---|---|
| 1 inch | centimeters | 2.54 cm |
| 1 mile | kilometers | 1.609 km |
| 1 kilogram | pounds | 2.205 lb |
| 0°C | Fahrenheit | 32°F |
When precision actually matters
For everyday use — checking a weather forecast or converting a recipe — a rough approximation is usually fine. But for anything more exacting, like engineering measurements, medication dosages, or shipping weight limits with a strict cutoff, using exact conversion factors rather than rounded rules of thumb (like "just multiply by two" for kilograms to pounds) can matter. This tool always uses the precise, standard conversion factor rather than a simplified approximation.
Frequently asked questions
+Is this unit converter really free, with no sign up?
Yes. There's no account and no limit on how many conversions you can do.
+Which units does this converter support?
Length (millimeters, centimeters, meters, kilometers, inches, feet, yards, and miles), weight (milligrams, grams, kilograms, ounces, and pounds), and temperature (Celsius, Fahrenheit, and Kelvin).
+How accurate are the conversions?
Exact, using standard conversion factors — for example, 1 inch is defined as precisely 2.54 centimeters, and that's the value used here rather than a rounded approximation.
+Why do I need three separate categories instead of one converter?
Length, weight, and temperature don't share a common unit to convert through — length is based on distance, weight on mass, and temperature uses different scales entirely (including one, Fahrenheit, that isn't just a multiplied version of Celsius). Keeping them separate avoids any confusing or invalid conversions between incompatible types.
+Is my data sent anywhere when I use this?
No. Every conversion is calculated directly in your browser — nothing you type is ever uploaded or logged.