🔢 Number Base Converter

Using Number Base Converter

Convert whole numbers between decimal, hexadecimal, binary, octal and any base from 2 to 36 when reading memory addresses, permissions, color codes or bit flags.

How to use it

1. Type into whichever field matches your number: Base 10 Decimal, Base 16 Hexadecimal, Base 2 Binary or Base 8 Octal.
2. Read the other three fields, which update as you type.
3. For another base, move the Custom Radix slider (2 to 36) and read Result in Custom Base.
4. Copy the representation you need with its Copy button.

Worked example

Input and settings

255 in Base 10 Decimal; custom radix 36

Expected result

ff (hex), 11111111 (binary), 377 (octal), 73 (base 36)

Limits and common mistakes

• Only whole numbers work: 12.5 shows an error because . is not a digit.
• Very large integers are handled exactly (18446744073709551615 becomes ffffffffffffffff).
• Negative numbers are shown with a minus sign, not as two's-complement bit patterns.
• Prefixes such as 0x or 0b are not part of the number; leave them out.

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