Convert between binary, octal, decimal and hexadecimal, and explore number bases.
Programmers live across number bases every day, and switching between them is one of the most common small tasks in the field. Binary (base 2) expresses bits and masks, octal (base 8) is the compact form of Unix file permissions, decimal (base 10) is everyday math, and hexadecimal (base 16) represents colors, memory addresses and hash digests. DevToolbox provides both a general base converter that handles any base from 2 to 36 and a set of focused converters for the pairs people reach for most, so you can translate a value without working it out by hand. Every conversion runs locally in your browser using BigInt-aware parsing, which keeps very large values exact instead of letting them lose precision the way ordinary floating-point math would. When you are reading a permission string such as 755, debugging a CSS color, or interpreting a memory offset, these tools show the translation and explain the base behind it. Hex, octal and binary literals may be written with 0x, 0o or 0b prefixes; the converters accept those prefixes and also output clean values you can paste straight into code. Conversion is exact and reversible, so you can translate a number to inspect it and then translate it back to confirm nothing was lost.
Number Base Converter
Convert a number between any two bases from 2 to 36, entering the source and target base.
Example
255 (base 10) → ff (base 16)
Max base?
Supports bases up to 36 using 0-9 and a-z.
Binary to Hex
Convert binary to hexadecimal, grouping bits into nibbles.
Example
11111111 → ff
Why group?
Each hex digit is four bits.
Binary to Decimal
Convert a binary string to its decimal value.
Example
1010 → 10
Common use?
Reading bit flags.
Decimal to Binary
Convert a decimal number to binary representation.
Example
10 → 1010
Negative numbers?
Two's complement is not applied; magnitude only.
Decimal to Hex
Convert decimal to hexadecimal, the format of colors and addresses.
Example
255 → ff
Used for?
CSS colors, memory offsets.
Hex to Decimal
Convert a hexadecimal value back to decimal.
Example
ff → 255
Prefix?
0x is optional.
Octal to Decimal
Convert octal (base 8) to decimal, useful for Unix file permissions.