JWT decoder
Inspect a JWT header, payload and expiry without asserting authenticity. Use JWT decoder locally with practical instructions, output settings and format limits.
JWT decoder
Inspect a JWT header, payload and expiry without asserting authenticity. A readable payload does not establish authenticity. The report explicitly says signatureVerified is false, and expiry is compared with the current computer clock. Paste UTF-8 text into the main input or upload a matching file. A selected file takes priority over the pasted text.
- Read a JWT header and JSON payload during debugging.
- Compare expiry with the current computer clock.
- Inspect claims while keeping signature verification a separate step.
How to use JWT decoder
Provide the source
Paste UTF-8 text into the main input or upload a matching file. A selected file takes priority over the pasted text. Read the operation note before starting, because supported syntax and file limits are part of the result contract. The original file is not overwritten or renamed by this workflow.
Choose the intended result
This operation uses a fixed report format, so no extra output configuration is required. Change settings according to the file or text you actually supplied. Defaults are a starting point rather than a promise that every source uses the same conventions. A readable payload does not establish authenticity. The report explicitly says signatureVerified is false, and expiry is compared with the current computer clock.
Create and inspect the output
Use the main action button to run jwt decoder. Local processing checks the source and reports malformed or unsupported inputs. A completed job appears in Your results, with a download action and a preview when the output supports it. If the operation fails, read its message and correct the source or settings before retrying; changing only a filename does not change file contents.
Save and verify the result
Download the finished output and open it in the application or workflow that will consume it. Enter or upload the source, choose settings, then create and review your result. Check the values, layout, encoding or parsed structure relevant to your task. Keep the source when you may need another set of settings later. Temporary job downloads are session-owned and expire; saving your own copy is the way to retain a result.
Understand the settings
This operation uses fixed output settings. Choose and order the supported files as described above, then review the output notes.
Try jwt decoder with a small source
Try this source: eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJhbGljZSIsImV4cCI6MX0.abc. Use the initial settings, inspect the result and then change one setting to understand its effect. A readable payload does not establish authenticity. The report explicitly says signatureVerified is false, and expiry is compared with the current computer clock.
Check your result
Enter or upload the source, choose settings, then create and review your result. Decoding does not verify a signature, issuer, audience or token authenticity. Do not treat decoded claims as trusted. Open the saved output in the app or workflow where you plan to use it. Check one representative result before repeating the same settings with more files. The original files stay unchanged.
What to know before you start
- Decoding does not verify a signature, issuer, audience or token authenticity. Do not treat decoded claims as trusted.
- Upload one file with a combined size of at most 100 MB. The completed output must fit within 200 MB.
- Pasted text and uploaded text have operation-specific UTF-8 byte limits. Productivity tools accept up to 1 MiB (1,048,576 bytes); non-ASCII characters can use several bytes each. If a file is selected, it takes priority over pasted text.
- Jobs run one at a time with a 180-second deadline. Temporary files expire after approximately 30 minutes; download them before clearing or restarting the app.
JWT decoder: common questions
What does JWT decoder produce?
Inspect a JWT header, payload and expiry without asserting authenticity. A readable payload does not establish authenticity. The report explicitly says signatureVerified is false, and expiry is compared with the current computer clock.
Which source should I use?
Paste UTF-8 text into the main input or upload a matching file. A selected file takes priority over the pasted text. Supported file extensions are txt, md, markdown, json, csv, html, htm, css, js, sql, xml, yaml. The processing engine checks actual contents; a matching extension alone does not make malformed content valid.
Why did this input fail?
Decoding does not verify a signature, issuer, audience or token authenticity. Do not treat decoded claims as trusted. Check syntax, required inputs and the ranges shown next to settings. An error keeps unsupported data from being presented as a successful conversion. Correct the source and retry rather than repeatedly resubmitting an unchanged invalid input.
How should I check the download?
Enter or upload the source, choose settings, then create and review your result. Review the saved content in its destination application, including a typical case and any boundary values important to your use. A completed operation confirms processing finished; it cannot determine whether the supplied settings match your wider business requirements.
Does JWT decoder upload files to another service?
Processing happens on the local server on this computer, using installed libraries, models and native tools. The browser-to-localhost connection is required, but no third-party conversion service is used. Initial dependency setup can require internet access; conversions use the installed local assets.
Can I continue after changing pages?
Pending selections stay available while navigating inside the app. Use My files to return to a tool draft or its results. Reloading or closing the tab discards pending browser selections; temporary job results expire after approximately 30 minutes. Download finished files before restarting the local app.