Certificate Decoder

About Certificate Decoder

Certificate Decoder reads an SSL/TLS certificate in PEM format that you paste in and displays its contents in a readable form: subject, issuer, serial number, signature algorithm, validity period, and the list of Subject Alternative Names. It is useful for verifying that a certificate file you received from a CA is for the right domain before installing it, or for inspecting an old certificate.

How to use

1. 1 Enter the target you want to check (a domain, IP address, or URL) in the field provided.
2. 2 Click the run button - the request is processed on Computing ID servers and the results are shown in the panel.
3. 3 Read the results; copy the parts you need, or change the input and run it again to compare.

Free tools from Computing ID

Certificate Decoder is one of dozens of network, security, and developer utilities provided free of charge by Computing ID (PT Intprism Computing Technology). Every tool can be used without creating an account or logging in. For tools that run entirely in the browser, your data is never sent to our servers; for tools that need to call a server (such as a DNS lookup or SSL check), only the target you enter is processed, and it is not stored. If you need infrastructure to run your own services, Computing ID also offers Linux and Windows VPS, cPanel hosting, email hosting, S3 Object Storage, WireGuard VPN, and domain registration, with data centers in Indonesia and Singapore and 24/7 technical support.