Updated
Math
Base Converter Calculator
Convert numbers between bases 2–36, including binary, octal, decimal, and hexadecimal. Supports negatives, fractions, readable grouping, and conversion history with CSV export.
Base-to-Base Number Converter
Enter a value, choose the source and target base, and get conversions plus a clear breakdown.
Use digits 0–9 and letters A–Z (case-insensitive). Use “.” for fractional parts and “-” for negative values.
Quick Steps
- Enter a number (use A–Z for digits above 9) and an optional fractional part.
- Select the source base (From) and target base (To).
- Choose how many fractional digits to output in the target base.
- Convert, then optionally review the decimal/binary/hex references.
- Use History to compare conversions and export to CSV.
Tip: Some fractions can’t be represented exactly in another base (like 0.1 in decimal to binary), so the fractional output may be rounded to your chosen digit limit.
| Base | Name | Digits Used | Common Use |
|---|---|---|---|
| 2 | Binary | 0–1 | Computers, bit operations |
| 8 | Octal | 0–7 | Unix permissions, compact binary |
| 10 | Decimal | 0–9 | Everyday numbers |
| 16 | Hexadecimal | 0–9, A–F | Colors, memory addresses, debugging |
| 36 | Base-36 | 0–9, A–Z | Short IDs, URL slugs |
How Conversion Works
- Parse input into an integer part and a fractional part (if present), plus an optional sign.
- Convert to decimal by summing digit × base^position for the integer and digit ÷ base^position for the fraction.
- Convert from decimal to the target base:
- Integer part: repeated division by the target base.
- Fraction part: repeated multiplication by the target base.
- Format with optional grouping for readability.
For base 2, grouping by 4 can help you read binary as “nibbles.” For base 16, grouping by 2 can help you read “bytes.”
Your conversion history will appear here after you convert a number.