Number Base Converter
Convert numbers between binary, octal, decimal and hexadecimal — live, with every base shown at once.
Convert numbers between binary, octal, decimal and hexadecimal — live, with every base shown at once. Handles huge numbers with arbitrary precision and auto-detects 0x/0b/0o prefixes, so you can paste hex from code straight in.
How to use the Number Base Converter
- Type a number in any base (prefixes like 0x are auto-detected).
- Pick the input base or leave it on auto-detect.
- Read the value in binary, octal, decimal and hex at once.
Frequently asked questions
How do I convert binary to decimal?
Type the binary number, choose Binary as the input base, and read the decimal row — 1010 becomes 10.
How do I convert hex to decimal?
Paste the hex value (with or without 0x) and read the Decimal row instantly.
Can it handle 64-bit values?
Yes — conversions use arbitrary-precision integers, so values far beyond 64 bits convert exactly.
What does the Character row show?
The Unicode code point for the number, useful when decoding escapes like 0x1F600.
Fun facts about Number Base Converter
- The decimal system (base-10) likely became dominant because humans have 10 fingers — but base-12 (dozenal) has advantages because 12 is divisible by 2, 3, 4, and 6.
- Computers use binary (base-2) because transistors have two states: on and off. Every piece of data in a computer is ultimately represented as binary.
- Octal (base-8) was commonly used in early computing because 3 binary digits map to exactly 1 octal digit — but hexadecimal has largely replaced it.
- The Babylonians used a base-60 (sexagesimal) number system around 2000 BC — this is why we have 60 seconds in a minute and 360 degrees in a circle.
- Base64 encoding (used in data URIs and email attachments) uses 64 characters to represent binary data as text — it's not a number base in the traditional sense.