Number Base Converter Online — Binary Hex Decimal
Convert integers between bases 2 and 36 with BigInt precision. Live preview, swap bases, optional byte endianness, and auto 0x/0b/0o output prefixes — browser-local.
How conversion works
Enter a value in the input base (digits A–Z case-insensitive; 0x/0b/0o prefixes accepted when the input base matches). The result updates as you type. Byte endianness applies only when the output base is 2 or 16: the absolute value is padded to whole bytes and grouped (spaces). Use Swap to move the result back to the input pane and flip the bases. Auto output prefix adds 0x, 0b, or 0o for raw hex/binary/octal output — not for byte-grouped endian dumps.
Options
- Input base (2–36)
- How to interpret the typed digits. Presets cover binary, octal, decimal, and hex; other bases are available in the list.
- Output base (2–36)
- Target radix for the result. Default is hexadecimal for common debug workflows.
- Byte endianness (none / BE / LE)
- None prints raw digits (including a leading minus for negatives). BE/LE group padded bytes for hex or binary on non-negative values only — useful for masks and memory dumps. Disabled for other output bases.
Examples
Decimal → hex
Input
Output
Decimal → hex LE bytes
Input
Output
Related utilities
Encode binary-ish text with Base64, or explore bits via the regex tester for pattern masks.
Number base converter FAQ
Radix conversion questions
Why BigInt?
JavaScript Number loses precision above 2^53−1. BigInt keeps large integers exact for hex dumps and masks.
Are floats supported?
No — integers only. Fractions and IEEE floats are out of scope for this tool.
When does endianness apply?
Only for output bases 2 and 16. Other bases always print raw digits.
Is my value uploaded?
Never — conversion runs in your browser.
What does Swap do?
It copies the current result into the input pane (spaces stripped from byte groups) and exchanges the input and output bases — handy for round-trip checks.
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