Number Base Converter
Convert numbers between binary, octal, decimal, hexadecimal and any base up to 36, with all common bases shown at once.
Enter a value and choose bases
Bases above ten use digits 0–9 and letters a–z. Integer conversion is exact for values of any size.
Conversion result
Enter a value, choose bases and press Convert.
What is a number base?
A number base, or radix, says how many digits a numeral system uses. Decimal uses ten digits, binary uses two, octal uses eight and hexadecimal uses sixteen.
Programmers switch between bases to read memory addresses, bit masks and colour values, or to encode identifiers in a compact form.
How to convert a number base
- Type the value you want to convert.
- Choose the base it is written in and the base you want out.
- Press Convert.
- Read the converted value plus a table of binary, octal, decimal, hexadecimal, base 32 and base 36.
Base conversion examples
Decimal to hex
255 (base 10)
ff (base 16)
Binary to decimal
101010 (base 2)
42 (base 10)
A large integer
9007199254740993 (base 10)
20000000000001 (base 16)
Browser converter vs other ways
| Criterion | UrsaKit Base Converter | Calculator app | Programming a snippet |
|---|---|---|---|
| Bases supported | 2 to 36 | Usually 2, 8, 10, 16 | Any, with code |
| Large integers | Exact, uses BigInt | Loses precision | Depends on the language |
| Data leaves the device | No, runs in the browser | No | No |
Frequently asked questions
Is the base converter free?
Yes, with no account and no limit.
Which bases are supported?
Any base from 2 to 36, with a quick table for 2, 8, 10, 16, 32 and 36.
Does it lose precision on large numbers?
No. Integer conversion uses BigInt, so values larger than 2^53 stay exact.
Does it handle fractional numbers?
This version converts integers; fractional digits are not converted.
Are the letters case sensitive?
No. A and a are both valid for digit 10, and the output can be switched to uppercase.