Davemi ToolsNumber Base Converter
Convert between binary, octal, decimal, hexadecimal, and any base from 2 to 36 — instantly.
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How number bases work
A number base (or radix) is how many unique digits a system uses to represent values. Decimal — the everyday base 10 — uses digits 0–9. Binary (base 2) uses just 0 and 1, which is how computers store everything at the lowest level. Hexadecimal (base 16) packs four binary digits into one, so it's the compact shorthand you see in color codes, memory addresses, and byte dumps. Octal (base 8) groups three bits and still shows up in Unix file permissions.
Frequently Asked Questions
Which number bases are supported?
You can convert between binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16), plus any custom base from 2 to 36. Pick the base your input is written in, and every other representation updates instantly.
How big a number can I convert?
Conversions use BigInt under the hood, so there's no 64-bit limit — you can convert numbers with hundreds of digits without losing precision.
Does it handle negative numbers?
Yes. Prefix the value with a minus sign (for example -1010 in binary) and the sign is preserved across every base.
What happens if I type an invalid digit?
If a character isn't a valid digit for the base you selected — like the digit 2 in a binary number — the tool flags the input as invalid instead of guessing.
Is my input sent anywhere?
No. Everything runs locally in your browser — nothing is uploaded to a server.
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