SSL Certificate Notes

Read what a certificate contains.

Runs locallyNo signupMobile readyCopyableFree

🔐SSL Certificate Notes

All processing happens locally

Paste PEM certificate (with BEGIN/END lines)

Certificate info

SSL Certificate Notes is a tool for reading certificate details, the calculation runs in your browser, so your figures never reach a server.

Results update as you change any field; copy them into a sheet or quote.

Paste or type your content into the input field at the top, or press the sample button to load demo data.
Adjust the options below the input, such as output format, separators, letter case or precision.
Press the main button to run the conversion. Results appear instantly in the output panel without a page reload.
When the result looks right, use the copy button in the corner, or download it as a local file.

Clean up stray spaces and line breaks before pasting for more accurate results.

Why can it not check any site?+

Same-origin policy blocks scripts from reading another site's chain; only the serving host sees it. A static page cannot probe remote certificates.

How do I inspect a local one?+

Export the certificate as PEM or Base64 CER, paste it here, and the tool decodes subject, issuer, validity and SANs.

Is SSL Certificate Notes free to use?+

Yes. The tool is completely free with no usage limits, and you never need an account or a sign-in.

Is the text I enter uploaded anywhere?+

No. All processing runs locally in your browser, so the input never reaches a server and is never logged or stored.

Does SSL Certificate Notes work on a phone or tablet?+

Yes. The layout is mobile-first, so inputs and buttons stay comfortable on phones and tablets in both orientations.

Can I copy the result into my own document?+

Yes. A copy button in the output panel puts the result on your clipboard, and you can also download it as a text file.