SSLABOUTSSLaboutssl.info

THE TLS CERTIFICATE WORKBENCH

Know What Your
Certificate Is Saying.

Inspect a website’s public TLS certificate. Understand the expiry, identity and chain—then use the workshop to build the files you actually need.

01

ONE PUBLIC HOSTNAME

Inspect the Certificate

Use a hostname, not a URL or IP address. The check connects to one public address on port 443.

Read-only. No uploads.
Your private keys, PFX files and passwords stay on your own machine.
What Does This Check Cover?

One TLS 1.2 or 1.3 handshake, using the hostname for SNI. We report the certificate dates, hostname check, trust result and negotiated connection.

We do not scan ports, test every cipher, inspect revocation, or certify that a website is safe. Behind a CDN, this is the public edge certificate.

02

EVIDENCE, NOT A SECURITY SCORE

Your Certificate Snapshot

Ready to Read the Handshake.

Run a check to see real certificate information. No guessed expiry date or prefilled “secure” verdict.

  • Identity: subject names and hostname match.
  • Validity: issue date, expiry and days remaining.
  • Connection: TLS version, cipher and trust result.
  • Chain: certificate path with issuer details.
60 Requests / Minute / IPPages, assets and endpoints share this rolling allowance.
6 TLS Checks / Minute / IPOne check uses one lookup unit. Failed attempts also count.
CLI / API Guide →

THE CERTIFICATE WORKSHOP

From Private Key to Working PFX.

Practical OpenSSL and PowerShell steps. Every command runs on your machine—not on this website.

01 / READ THE RESULT

Understand the TLS Handshake.

Names, dates, trust and chains—what the checker can and cannot tell you.

5 min read02 / OPENSSL

Create a Key and CSR.

Encrypted keys, SAN names and clearly marked self-signed test certificates.

6 min read03 / WINDOWS

Work with PowerShell.

Create a test certificate, request a signed one, and export from the Windows certificate store.

7 min read04 / CERTIFICATE BUNDLES

Build the Complete PFX.

Match the key, verify the chain, and package the certificate and CA certificates together.

7 min read05 / FILE FORMATS

Convert Without Guesswork.

PEM, DER, CER, CRT, P7B and PFX—choose the conversion that preserves what you need.

5 min read06 / IN THE FIELD

Fix the Right Problem.

Missing keys, broken chains, hostname errors and renewal troubleshooting.

5 min read

THE PARTS OF A CERTIFICATE BUNDLE

One File. Different Responsibilities.

  1. Leaf certificateYour website’s identity and public key.
  2. Matching private keyThe secret your server must protect.
  3. Intermediate CA certificatesThe links from your certificate toward a trusted root.
  4. Root CA, when requiredIncluding it does not make it trusted.
Build and Verify a PFX →

TERMINAL FRIENDLY

Your Public IP. One Command.

The bare command returns your connection IP and one newline. Add the API path for a certificate report.

Terminal
curl aboutssl.info

The bare command uses HTTP. Use https://aboutssl.info for encryption.

Copy TLS and PowerShell Examples →