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Online Number Base Converter

Enter a number in any base — the rest update instantly. Handy for working with bitmasks, HEX colors, ASCII codes, and memory addresses.

DEC

Decimal

BIN

Binary

HEX

Hexadecimal

OCT

Octal

Bit representation — 8 bits (1 bytes)

11111111

255

Sign: unsigned uint8 · ASCII: non-printable · Color (if ≤ 0xFFFFFF): #0000FF

Frequently asked questions

Why convert numbers between different bases?

Binary (BIN) is the language of the CPU — bitmasks and flags. Hexadecimal (HEX) is used for colors (#FF5733), memory addresses, and bytecode. Octal (OCT) covers Unix file permissions (chmod 755). Decimal is everyday arithmetic.

How do I decode a HEX color into RGB?

#RRGGBB is three pairs of HEX digits. Enter the value in the HEX field (without #). For example, FF5733: FF = 255, 57 = 87, 33 = 51 → rgb(255, 87, 51). The converter shows the decimal value of each byte.

What is bitwise representation?

Bitwise (binary) representation shows every individual bit of a number. 8 bits = 1 byte. For 255: 11111111 (all bits set). For 128: 10000000 (only the most significant bit). Used when working with bitmasks and bit flags.

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