Universal Decoder
Decode text using URL, Base64, JWT, Hex, Unicode, Binary, ROT13, or HTML entity encoding — pick a scheme from one dropdown instead of using a separate tool for each.
Input
Output
Guides
What this tool does
One decoder, eight schemes: URL (percent-decoding), Base64, JWT, Hex, Unicode (\uXXXX), Binary, ROT13, and HTML entities. Pick a scheme from the dropdown instead of hunting down a separate tool for each one. Everything runs entirely in your browser — nothing is uploaded.
How to use it
- Paste the encoded value into the input box.
- Choose the scheme it's encoded with.
- Read the decoded result. Copy it or download it as a
.txtfile.
Frequently asked questions
Does it verify a JWT's signature? No — JWT decoding here is inspect-only. It splits the token, base64url-decodes the header and payload, and shows both as pretty-printed JSON (plus the raw signature segment for reference). It never checks whether the signature is valid, the same scope as the dedicated JWT Decoder.
Which tool should I use if I only ever decode one format? The dedicated single-scheme tools have more options: URL Encoder / Decoder, Base64 Decode, JWT Decoder, Hex to Text Converter, Binary to Text Converter, ROT13 Encoder / Decoder, and Unicode to HTML Entities. This tool exists for switching between schemes without changing pages.
How tolerant is hex parsing?
It accepts space, comma, dash, 0x, \x, or no separator at all — you don't need to pick a format first.
Is my input ever sent anywhere? No — every scheme here (including JWT inspection) runs as a pure, synchronous function in your browser. Nothing is uploaded to a server.
Need to encode instead? Use the matching Universal Encoder.
Use it from code
From 3 credits per callREST API
curl -X POST https://api.iotools.cloud/v1/tool/universal-decoder \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"inputText": "SGVsbG8sIFdvcmxkIQ==",
"scheme": "base64"
}'Swap in your own key from your account. The tool's fields are the body — no wrapper.
Ask an AI agent
Use the IOTools `universal-decoder` tool (Universal Decoder) on this input:
YOUR_INPUT_HEREPaste this at any agent connected to the IOTools MCP server, then add your input.