Number Systems for Computer Science

Learn and verify binary, octal, hex conversions — perfect for CS students and exam prep.

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Input base:

Decimal number

Quick values

Education tips

🎓

Computer science courses cover all four bases. Use the quick-value buttons (7, 8, 15, 16) to explore where the boundaries between bases are.

💡

Why hex? 1 hex digit = exactly 4 binary digits (a "nibble"). 2 hex digits = 1 byte (8 bits). This makes hex a compact way to write binary.

🔢

Octal (base 8) groups binary digits in sets of 3. Less common today but still used in Unix file permissions (chmod 755 = rwxr-xr-x).

📊

Use the grouped binary output to visualise how nibbles (4-bit groups) map to hex digits — it makes the hex↔binary relationship intuitive.

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