How to convert between bases
- Pick the input base (for example 16 for hex).
- Type the number using digits valid for that base.
- Read binary, octal, decimal, and hex in the output rows.
- Copy one row or copy all formatted lines.
Uppercase and lowercase letters are the same for bases above 10. You may separate digit groups with spaces or underscores; they are stripped before parsing.
Validation rules
Each character must be a valid digit for the input base. In base 2 only 0 and 1 are allowed. In base 8, digits stop at 7. In base 16, use 0-9 and A-F.
A lone + or − without following digits is an error. After a valid parse, outputs update live as you type.
Privacy
No account and no upload. Large integers use the same BigInt math as modern JavaScript; practical limits follow what your device can handle in a text field.