QuickUnitsConverter

Unit Converter

Frequently Asked Questions

How does the live conversion work?
Every unit stores a single conversion factor relative to a shared base unit (e.g. grams for weight, seconds for time). When you type in any field, the value is converted to that base and then propagated to every other field in real time — no dropdowns, no submit button needed.
How accurate are the conversions?
Linear conversions (length, weight, area, volume, time) use internationally-defined exact factors (e.g. 1 inch = 2.54 cm exactly). Results are displayed rounded to 8 significant figures in full decimal notation — no scientific notation. Number-system conversions (binary, octal, hex) use BigInt arithmetic so there is zero precision loss even for very large integers.
Why does temperature work differently?
Unlike length or weight, temperature scales have both different zero points and different step sizes. For example, 0 °C = 273.15 K ≠ 0 K. Internally, Kelvin is used as the base: input is first converted to Kelvin, then projected to every other scale. The formulas are: °C = K − 273.15 and °F = (K − 273.15) × 9/5 + 32.
What number bases are supported?
Binary (base 2), Octal (base 8), Decimal (base 10), and Hexadecimal (base 16). Hex input is case-insensitive — type ff or FF, both work. If you type an invalid digit for the selected base (e.g. a 2 in binary) the field turns red and other fields stay clear until the input is valid.
Is this free? Does it need an internet connection?
Completely free, no account needed. All conversions run entirely in your browser — no data is ever sent to a server. After the page loads, fonts and the Tailwind CDN script are the only external dependencies; the conversion math itself works fully offline.
Does it work on mobile?
Yes. The tab bar scrolls horizontally on small screens, unit cards stack into a single column, and numeric inputs use inputmode="decimal" to trigger the number keypad on iOS and Android. The hex field uses a standard text keyboard.

Contact Us

Have a suggestion, found a bug, or want a new unit or category added? We'd love to hear from you.

We typically respond within 1–2 business days. Feature requests for new unit categories are always welcome.