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Number Base Converter

Convert numbers between binary, octal, decimal and hexadecimal simultaneously — type in any base and all others update instantly.

Binary (base 2) Octal (base 8) Decimal (base 10) Hex (base 16) Live conversion Bit display
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Quick reference — same value, all bases

Decimal Binary Octal Hex
0 0 0 0
1 1 1 1
8 1000 10 8
10 1010 12 A
15 1111 17 F
16 10000 20 10
127 1111111 177 7F
255 11111111 377 FF
256 100000000 400 100

Frequently asked questions

Why do programmers use hexadecimal?

Each hex digit represents exactly 4 binary bits (a nibble). This makes hex a compact readable representation of binary data. A byte (8 bits) is always exactly 2 hex digits. This is why memory addresses, color codes (#FF5733), MAC addresses and byte dumps are shown in hex — easier to read than binary and maps directly to the underlying bits.

What is two's complement for negative numbers?

Two's complement is the standard way computers represent negative integers. For a signed 8-bit integer, the range is -128 to +127. To negate a number: invert all bits and add 1. Example: 5 is 00000101; -5 is 11111011. Two's complement makes addition and subtraction work identically for positive and negative numbers.

What is endianness?

Endianness describes the order bytes are stored in memory. Big-endian stores the most significant byte first. Little-endian stores the least significant byte first (used by x86/x64 processors). Network protocols use big-endian (network byte order). Endianness matters when reading binary files or network packets across different architectures.

How do bitwise operators use binary?

Bitwise operators work on the binary representation: AND (&) is 1 only where both bits are 1; OR (|) is 1 where either bit is 1; XOR (^) is 1 where bits differ; NOT (~) flips all bits; left shift (<<) multiplies by powers of 2; right shift (>>) divides. Common in flags, compression and cryptography.

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Convert any number between bases

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