Unit & Data Converter
Convert units, number bases, and CSV/JSON data — instantly in your browser.
Convert length, weight, and temperature units, convert numbers between binary, octal, decimal, and hexadecimal, or convert between CSV and JSON — three converters used constantly by developers and anyone working with spreadsheets, in one place.
How to convert units
- 1Pick a category from the dropdown: Length, Weight, or Temperature.
- 2Type a number into the "From" field.
- 3Choose the unit you're converting from and the unit you're converting to using the two dropdowns.
- 4The converted value updates instantly in the "To" box — no button to press.
- 5Use the ⇄ button to swap the From and To units if you want the conversion the other way round.
Frequently asked questions
How accurate are the conversions?
Length and weight conversions are computed from precise conversion factors and rounded to 8 decimal places. Temperature conversions use the exact Celsius/Fahrenheit/Kelvin formulas, rounded to 4 decimal places.
Can I convert between different categories, like length to weight?
No — the unit dropdowns only show units from the category you've selected, since converting length to weight (for example) isn't a valid operation.
Why does the To field show a dash (—)?
That means the From field is empty or isn't a valid number. Type a numeric value to see the converted result.
Is my data sent anywhere when I convert a value?
No. The conversion math runs entirely in your browser with plain JavaScript — nothing you type is ever sent to a server.