Hex Converter
Convert hex to decimal, binary and octal, or any of them back to hex. Type a value below: a 0x prefix or any A-F digit switches the input to hex, and every result stays exact at any length.
2550xFF0b111111110o377How Hex Conversion Works
Hexadecimal is base 16: the digits 0-9 then A-F for ten to fifteen. Each hex digit is exactly four binary bits, so a hex number converts to binary digit by digit, and to decimal by multiplying each digit by its power of 16 (FF = 15 × 16 + 15 = 255).
- 0
- 0
- 0000
- 1
- 1
- 0001
- 2
- 2
- 0010
- 3
- 3
- 0011
- 4
- 4
- 0100
- 5
- 5
- 0101
- 6
- 6
- 0110
- 7
- 7
- 0111
- 8
- 8
- 1000
- 9
- 9
- 1001
- A
- 10
- 1010
- B
- 11
- 1011
- C
- 12
- 1100
- D
- 13
- 1101
- E
- 14
- 1110
- F
- 15
- 1111
Need every byte at once? Print the 0-255 hexadecimal chart.
Bit-Level Developer Tools, Exact at Any Width
Registers, masks, floats, and checksums - plus base conversion with arbitrary precision. Every integer path runs on BigInt, never a float, so 64 and 128-bit values stay exact to the last digit.
Bits & Bytes
Registers, masks, floats, and checksums - the bit-level toolkit
Convert Numbers
Base conversion with arbitrary precision - exact beyond 2^53
Text & Encoding
ASCII, Unicode, and binary text encodings
Networking & Utils
Subnets, IP addresses, UUIDs, hashes, and timestamps
Math Tools
Ratios, percentages, and number systems
References Worth Bookmarking
Methodology & Correctness
Why every integer path uses BigInt, input limits, and how results are tested.
Base Conversion Test Vectors
Verified 2^53-boundary and 64/128/256-bit vectors, generated from tested code.
Number Literal Syntax Matrix
0b / 0o / 0x literals, BigInt, and parse functions across seven languages.
Printable Hexadecimal Chart
Every byte 0-255 in hex, decimal, binary and octal on one printable page.
Printable ASCII Chart
All 128 ASCII codes with binary, hex and octal, sized for one A4 or Letter sheet.
Built for Developers
Exact Beyond 2^53
BigInt end to end. 64, 128, 256-bit values convert without losing a single digit - and we label when plain numbers stop being safe.
100% Client-Side
All processing in your browser. Your data never leaves your device.
Code-Ready Output
Signed views, endian bytes, and copy-ready snippets in JS, Python, Go, Rust, C, and shell.