Unit converter

Length, weight, temperature, area, volume, speed and data sizes — type a value and see it in every unit of the category at once.

This tool runs entirely in your browser — nothing you type or open here is ever uploaded. You can disconnect from the internet after the page loads and it still works.

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More utilities & calculators

🔢 Number bases

Binary, octal, decimal, hex — arbitrary precision.

🎲 Random number

True random numbers in any range, with or without repeats.

🪙 Coin flip

A fair coin — exactly 50/50, with a running tally.

🎲 Dice roller

d4 to d100, one die or a handful, fairly rolled.

⏱️ Stopwatch

Precise stopwatch with laps, right in the tab.

⏲️ Countdown timer

Beeps when done; the tab title shows the time left.

See all 80 tools →