Identify SSL/TLS version used by an Browser HTTPS Secure Connection

When making a connection using HTTPS, either SSL or TLS will be used to encrypt the information being sent to and from the server. This encryption makes it very difficult for a third party to read the data packets. The information is encrypted using a Cipher or encryption key, the type of Cipher used depends on the Cipher Suite installed and the preferences of the server.

This post describes how to find the Cipher used by an HTTPS connection, by using Microsoft Edge, Google Chrome or Mozilla Firefox, to show the current cipher suite and certificate information.

How to find the Cipher in Microsoft Edge Chromium

1. Launch Microsoft Edge.
2. Enter the URL you wish to check in the browser.
3. Click on the three-dots on the top-right (Alt+F) in the browser.
4. Select More tools > Developer tools > Security (Ctrl+Shift+I).

How to find the Cipher in Google Chrome

1. Launch Google Chrome.
2. Enter the URL you wish to check in the browser.
3. Click on the three-dots on the top-right (Alt+F) in the browser.
4. Select More tools > Developer tools > Security (Ctrl+Shift+I).

How to find the Cipher in Firefox

1. Launch Firefox.
2. Enter the URL you wish to check in the browser.
3. In the address bar, click the icon to the left of the URL.
4. Now click on Connection secure > More Information.

How to find Cipher using OpenSSL

If you are using a Linux machine and the OpenSSL library is available on the preferred system, you can use the command in the example below.

openssl s_client -connect think.unblog.ch:443 | find "Cipher"

The next command causes openssl to produce the following output.

$ openssl s_client -verify_quiet -brief think.unblog.ch:443
depth=2 C = US, O = Internet Security Research Group, CN = ISRG Root X1
CONNECTION ESTABLISHED
Cipher Protocol version: TLSv1.3
Ciphersuite: TLS_AES_256_GCM_SHA384
Peer certificate: CN = unblog.ch
Hash used: SHA256
Signature type: RSA-PSS
Server Temp Key: X25519, 253 bits