Number Base Converter
Convert values between binary, octal, decimal, and hexadecimal with BigInt precision and optional 0b/0o/0x prefixes. Built for bitmasks, color values, and low-level debugging without float rounding surprises.
Runs entirely in your browser. Your data never leaves this device.
- Bin / Oct / Dec / Hex
- BigInt precision
- Prefix support
- Live sync
- Dev-friendly
How it works
- Enter a number in any base (2, 8, 10, or 16).
- See live conversions across bin/oct/dec/hex.
- Copy the representation you need for bitmasks, colors, or debugging.
Key features
- Bin / Oct / Dec / Hex
- BigInt precision
- Prefix support
- Live sync
- Dev-friendly
FAQ
Big integers?
We use BigInt where possible so large hex values do not lose precision like IEEE floats.
Prefixes?
0b/0o/0x prefixes are accepted and optional in output.
Negative numbers?
Decimal negatives are supported; two’s-complement bit views are not the focus of this MVP.
Private?
Yes — local conversion only.
Keep building
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