Convert Numbers for Programming

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

ログイン不要

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.

入力

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

処理

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

ダウンロード

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