Numbers can be written in many bases, and developers constantly switch between them: hexadecimal for colors and memory addresses, binary for flags and bitmasks, octal for file permissions, and decimal for everyday math. The ToolOrbit Number Base Converter moves a value between binary, octal, decimal, and hexadecimal instantly, and it is BigInt-safe so huge numbers stay exact.
How positional bases work
Every base assigns place values as powers of that base. In base 10 the digit positions are ones, tens, hundreds. In base 2 they are ones, twos, fours, eights. Hexadecimal uses sixteen symbols, 0-9 then A-F, so a single hex digit packs four binary bits, which is why hex is such a convenient shorthand for binary data.
decimal 255 binary 11111111 octal 377 hex FF
Why BigInt safety matters
- JavaScript numbers lose precision above 2^53, silently corrupting large values
- BigInt arithmetic keeps every digit exact, no matter how long the number is
- This is essential for 64-bit IDs, cryptographic values, and large bit fields
- The converter handles arbitrarily long inputs without rounding errors
Using the converter
Type a value into any base field and the others update at once. You do not need to add prefixes like 0x or 0b; just enter the digits for that base. All computation happens locally in your browser, so even large or sensitive values never leave your machine.
Common uses
Reach for the converter when decoding a hex color, reading a permission mode such as 755 in octal, inspecting a bitmask, or sanity-checking a memory address. Keeping a quick base converter at hand removes a whole category of off-by-one and place-value mistakes.
Hex and binary you meet daily
| Decimal | Hex | Binary |
|---|---|---|
| 10 | 0xA | 1010 |
| 15 | 0xF | 1111 |
| 255 | 0xFF | 11111111 |
| 4095 | 0xFFF | 111111111111 |
IPv6 addresses, MAC addresses, color values (#FF8800 is just hex), URL percent codes and git object names are all hex in disguise. Binary shows up in flags and bitmasks. Learn “0xF = 1111” and the pattern extends everywhere: 0xFF = 1111 1111, 0xFFF = three nibbles. That is the whole trick — you read hex one nibble at a time.
One more everyday use: CSS colors, MAC addresses and IPv6 literals are all hex, and git short hashes are hex in miniature. Converting a color like #6c7bff to decimal RGB (116, 123, 255) is the same three two-digit hex pairs you now recognize — the converter just does the pairing for you.
