Convert Numbers for Programming

Convert between binary, octal, decimal, and hex while writing code — instant reference for any number.

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Input base:

Decimal number

Quick values

Programming tips

💻

Programmers frequently need to convert between decimal (what humans use) and hex (memory addresses, colours, bit flags).

💡

0xFF is 255 in decimal and 11111111 in binary — a fully set byte. The "Quick values" panel shows common programming constants like 127, 255, 65535.

🔢

The bit-size panel shows whether your number fits in 8, 16, or 32 bits — useful when working with typed arrays or protocol buffers.

🎨

CSS hex colours are base-16: #1A2B3C = R:0x1A (26), G:0x2B (43), B:0x3C (60). Convert each channel separately to inspect the colour.

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Enter your data into the tool above. Everything stays local to your browser.

Proses

The tool processes your data instantly in your browser using JavaScript. No server, no waiting.

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Get your result instantly. Nothing is stored after you leave the page — complete privacy.

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Convert Numbers for Networking

Convert subnet masks, port numbers, and IP address

Number Systems for Computer Science

Learn and verify binary, octal, hex conversions —

Inspect Bit Patterns and Flags

Convert numbers to binary to inspect individual bi

Decode Hex Dumps and Debug Logs

Decode hexadecimal values from crash reports, memo