JWT Decoder tool

JWT Decoder Online

Decode JWT header and payload locally in your browser. No signup is required.

Open tool

Browser tool

Paste or upload content

The input is processed locally in your browser. You can copy, download, or share the result.

Paste or upload content, then run the tool.

When to use this JWT decoder

Use this JWT decoder to inspect the header and payload of a token during debugging, documentation, or integration review. It is designed for everyday web, data, and developer workflows where a quick browser-side result is more convenient than opening a heavy desktop application.

The best workflow is to paste a small representative sample first, confirm the output looks correct, and then process the full content if it is appropriate to handle in your browser.

Example

JWT Decoder Online example

Use this before-and-after sample as a quick reference for what the tool changes.

Input example

eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjMifQ.signature

Output example

{"header":{"alg":"HS256"},"payload":{"sub":"123"}}

Review checklist

Common mistakes to avoid

Treating decoded JWT data as verified

Review this point before copying the output into another system, committing it to a project, or sending it to someone else.

Sharing production tokens with private claims

Review this point before copying the output into another system, committing it to a project, or sending it to someone else.

Ignoring token expiration or signature validation

Review this point before copying the output into another system, committing it to a project, or sending it to someone else.

Privacy and local processing

This JWT decoder runs in your browser. The page uses client-side JavaScript to process pasted text or uploaded files, and it does not require an account. Share links can include the content you entered, so only create or send a share link when the content is safe for the recipient to view.

For private projects, remove passwords, API keys, access tokens, personal information, customer records, and internal identifiers before using any online utility.

FAQ

JWT Decoder Online FAQ

Does this tool upload my file?

The tool is designed to process content in your browser with client-side JavaScript. You should still avoid using sensitive files in any browser-based tool unless you are comfortable handling that data there.

Can I download the result?

Yes. After running the tool, use Download output to save the processed content as a local file.

Can I share the result?

Yes. Use Share link to copy a link containing the current input and output. Only share it with people who should see the content.