Developer Tools
Convert positive, negative and very large integers between base 2, base 8, base 10 and base 16 without floating-point rounding. See every representation together and copy the value you need.
Integers only, with up to 4,096 digits. Matching 0b, 0o and 0x prefixes are optional.
Simple workflow
How to use Number Base Converter
- 1Enter an integer and choose its Source base.
- 2Select Convert integer. Matching 0b, 0o or 0x prefixes are optional.
- 3Review the exact binary, octal, decimal and hexadecimal forms and copy any result.
Good to know
Frequently asked questions
Can this converter handle integers larger than JavaScript's safe-number limit?
Yes. It uses exact BigInt integer arithmetic instead of floating-point Number conversion. Input is capped at 4,096 digits to keep very large values from consuming unreasonable browser resources.
How are negative integers represented?
Each output uses a leading minus sign, such as -2A in hexadecimal. This tool does not choose a bit width or produce a fixed-width two's-complement representation.
Can I convert fractional binary or hexadecimal values?
No. This version accepts integers only. A decimal point is rejected rather than rounded or silently removed.
Can I enter 0b, 0o or 0x prefixes?
Yes, when the prefix matches the selected Source base. A conflicting prefix produces an error so the converter never guesses which base you intended.
Practical guide
Read the same integer in four common number systems
Binary uses two digits, octal uses eight, decimal uses ten and hexadecimal uses sixteen. Developers use these bases for bit values, file permissions, addresses, colours and compact representations of machine data.
UtilSprout parses the input as an exact integer and produces every base from that one value. It uses BigInt arithmetic, so a valid value larger than JavaScript’s Number safe-integer limit is not rounded.
Worked example
Convert decimal 255
- Start with
- 255 with Decimal (base 10) selected.
- Choose
- Select Convert integer.
- You get
- Binary 11111111, octal 377, decimal 255 and hexadecimal FF.
Tips for a useful result
- Choose the source base before converting; invalid digits are rejected.
- Use 0b, 0o or 0x only when the prefix agrees with the selected base.
- Negative outputs use a minus sign, not a fixed-width two’s-complement pattern.
Prefixes, limits and privacy
The common prefixes 0b, 0o and 0x identify binary, octal and hexadecimal input. They are optional. The converter accepts integers only and limits input to 4,096 digits to bound browser work.
All parsing, conversion and copying happen in this page. The integer is not placed in a URL, stored in browser storage or sent to an API.
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