File & Format Converters · Free tool
Binary Converter
Convert between decimal, binary, octal, and hex live. Edit any field; the others update. Free, browser-only.
Updated May 2026
Negative numbers are allowed (sign-magnitude form). Hex is case-insensitive on input; output uses lowercase. Whole numbers only — fractional binary not supported.
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What it does
Decimal ↔ binary ↔ octal ↔ hex. Edits in any field flow to the other three live. Per-base validation so non-binary digits in the binary field don’t silently coerce. Negative numbers supported.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/binary-converter" width="100%" height="720" frameborder="0" loading="lazy" title="Binary Converter" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Type a number in any of the four fields.
- The other three convert instantly.
- Invalid characters for that base are silently rejected.
Frequently asked questions
- What's the largest number supported?
- JavaScript's parseInt is reliable up to about 2^53 in decimal — beyond that, integer precision is lost. For most practical needs (file sizes, color codes, IPs) this is far more than enough.
- Is hex case-sensitive?
- Input accepts both — '2A' and '2a' both parse to 42. Output uses lowercase by convention (matches CSS hex colors).
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