Number Base Converter
Convert integers between decimal (base 10), binary (base 2), octal (base 8), and hexadecimal (base 16) simultaneously. Type in any field and all others update instantly. Runs in your browser.
Convert an integer-like value among decimal, binary, octal, and hexadecimal fields. Editing one field updates the others using JavaScript integer parsing and formatting.
How to convert number bases
- Enter a value in the decimal, binary, octal, or hexadecimal field.
- The tool parses the field using its corresponding base.
- Read the converted values in the other fields.
- Use a copy button to copy a result.
Conversion behavior and limits
The implementation strips 0b or 0B for binary, lowercase 0o for octal, and 0x or 0X for hexadecimal before parseInt(). Uppercase 0O is not stripped.
JavaScript Number is used, so very large integers can lose precision, and parseInt() can accept a valid leading portion before an invalid trailing character.
Privacy and limitations
Conversion happens entirely in the browser. This is a JavaScript Number-based convenience converter, not an arbitrary-precision integer tool or strict whole-string syntax validator.
Number Base Converter FAQ
Which bases are supported?
Decimal, binary, octal, and hexadecimal.
Which prefixes are accepted?
0b/0B, lowercase 0o, and 0x/0X are stripped by this implementation.
Is uppercase 0O accepted as an octal prefix?
No. The current code does not strip uppercase 0O.
Does it support fractions?
No. It is based on parseInt().
Can very large integers lose precision?
Yes, because JavaScript Number is used.