Decode binary, hexadecimal or base64 input with automatic format detection. Particularly useful when you have an unknown encoded string and need to know which encoding it uses.
When debugging APIs, network protocols, or stored data, you often encounter encoded strings without knowing their format. A multi-format decoder tries common encodings (binary, hex, base64) and converts to plain text. Auto-detection works because each format has distinct character set restrictions: binary uses only 0/1, hex uses 0–9 and a–f, base64 uses A–Z, a–z, 0–9, + and /.
Paste your encoded string and pick a format (or leave Auto-detect). The tool inspects the input characters, picks the most likely format if Auto, and runs the appropriate decode function: parseInt(_, 2) for binary, parseInt(_, 16) for hex, atob() for base64. The decoded text shows below.
Use it when reverse-engineering API responses, when debugging cookies and tokens, when parsing data exports from legacy systems, when investigating obfuscated user data, and when teaching the differences between common encodings.
If auto-detect picks the wrong format, override manually with the dropdown. For complex multi-stage encodings (base64 of binary of text, for example), decode one layer at a time. For encrypted content (not just encoded), you need the decryption key — no tool can decrypt without it.
Base64 is a binary-safe text encoding — it can encode any byte sequence, including encrypted bytes. The decoded output may not be readable text if the source was encrypted or compressed.
No — both uppercase and lowercase hex digits are accepted.
Likely a wrong format choice or compressed/encrypted source data. Try the other formats; if all fail, the data isn't simply encoded.
Explore more binary converter tools on the tool hub — or jump straight to the Text To Binary, Binary To Text.