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Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal instantly.

Runs 100% in your browser — nothing is uploaded

About this tool

The Number Base Converter translates any integer between binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). Choose the input base, enter your number, and see all four representations simultaneously.

Number base conversion is a foundational concept in computer science and daily programming: understanding that 0xFF = 255 = 11111111₂ = 377₈ matters for bitwise operations, color codes (#FF0000 = RGB 255,0,0), permissions (chmod 755 = 111 101 101₂), memory addresses, network masks (255.255.255.0 = 0xFFFFFF00), and assembly programming.

Frequently asked questions

Why is hexadecimal so common in programming?
One hex digit represents exactly 4 bits. Two hex digits represent one byte (8 bits). This makes hex a compact, readable representation of binary data, used everywhere from color codes (#RRGGBB) to memory addresses (0x00000000).
What is the maximum number this tool can convert?
JavaScript safe integers are up to 2^53-1 (9,007,199,254,740,991). Numbers beyond this may lose precision. For very large numbers (cryptographic keys, etc.), use a BigInt-based tool.

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