First value · other representations
Numbers & representations
How it works
A positional number system assigns each digit a power of its base. Decimal 255 is FF in hexadecimal and 11111111 in binary. Changing base changes the representation, not the underlying value.
What you can do
Choose independent input and output bases, convert a batch and compare the first value in four common bases. Matching 0b, 0o and 0x prefixes are accepted. Letters A–Z represent digits 10–35.
How to use it
- Set input base and output base. For decimal 255 to hexadecimal FF, choose 10 and 16.
- Paste one value per line or open a UTF-8 text file.
- Select Convert, inspect the result, then copy or download TXT. Changes clear old results. Undo restores your previous input and settings.
Errors and limits
Integers and fractions use exact rational arithmetic. Parentheses mark repeating digits, for example 0.1(6). An ellipsis (…) means the selected output limit truncated a nonterminating fraction; it cannot be reused as an exact input. A minus sign denotes signed magnitude. No scientific notation.
Limits: 200,000 input characters, 500 values and 1,000,000 output characters. The entire batch stops on an invalid line.
Each numeric input accepts at most 1,000 digits. Intermediate integer arithmetic is bounded to 16,384 bits.
Frequently asked questions
Why does a large number change in some converters?
Floating-point arithmetic cannot represent every integer above 9,007,199,254,740,991. This converter uses integer arithmetic throughout, so 9007199254740993 becomes 20000000000001 in hexadecimal.
Are my values uploaded?
No. Processing and file reading happen in this browser tab. Values are not placed into URLs or sent to a conversion service. Downloaded files remain under your control.