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SSL Certificate Checker
- Does your website have SSL encryption?
- Is your website secure?
SSL brings success and security to your website
SSL Starter
- Protection for one domain name
- Domain Validation
- Up to 256-bit encryption
- Green padlock display
- Easy to activate
SSL Business
- Protection for one domain name
- Organisation Validation
- Up to 256-bit encryption
- Green padlock display
- Protection against phishing
SSL Premium
- GeoTrust True BusinessID EV
- Protection for one domain name
- Extended Validation
- Up to 256-bit encryption
- Green bar display
Check whether your SSL encryption is working
SSL Encryption
No SSL Connection.
SSL Validation
Certificate is installed correctly.
Eliminate errors and security gaps
Affected by Heartbleed or BEAST?
Warning. BEAST. The BEAST attack is not mitigated on this server.
The SSL checker examines the SSL configuration of the URL for any security gaps. Potential vulnerabilities include:
- POODLE
- FREAK
- BEAST
- CRIME
- Heartbleed
If the website entered does not pass the Heartbleed test, or one of the other security checks, our tool will let you know and provide advice on how to solve the problem.
Other possible errors
Installation and certificate information:
- No installation / faulty installation / wrong certificate
- Type, name, and validity of certificate (time period and status)
- Domain/Organisation, serial number and other information
Certificate chain:
- Which certified authority issued the certificate
- Who in turn has the certification body certified
Server configuration:
- Which security gaps can be detected in your current SSL version?
- Which algorithms (cipher suites) are used for key exchange, encryption and authentication?
SSL Checker
Once you have installed your SSL certificate, you can use the SSL test to make sure it is working properly. The check immediately shows whether your SSL certificate is installed correctly and valid. If this is not the case you will receive the notification "certificate is not installed correctly". Additionally you will receive a detailed analysis of your server configuration so you are aware of any problems or incompatibility and whether or not you need to modify your server configuration or use a different SSL certificate.
The last section of the SSL check shows a list of the cipher suites supported by your server configuration. Each row represents one cipher suite. A cipher suite is a combination of standard encryption algorithms that are used to protect the exchange of data. For the SSL protocol (and its successor TLS) a specific algorithm in the cipher suite is defined for each task: key exchange / authentication, hash function (a sort of fingerprint of the data that is to be exchanged) and encryption.
Example of a cipher suite: TLS_RSA_WITH_AES_256_CBC_SHA (0x0035). TLS describes the encryption protocol and the key exchange occurs via the standard RSA algorithm. AES (Advanced Encryption Standard) with 256 Bit in the CBC mode (Cipher Block Chain) is used for the encryption, while the hash function works with SHA. The bracket indicates the byte sequence.
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.app domain
Extended validation certificate
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.holiday domain
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.xyz domainUsing the SSL checker is particularly useful if you run a website that requires the exchange of sensitive data with your clients. This kind of data exchange should always be secured by an SSL certificate, as third parties might otherwise be able to gain access to the information. If you run an online shop where the checkout process requires the entering of a delivery address and payment details by the customer, or you host a contact form on your website where interested parties can enter their name and email address, an SSL certificate is vital.
If SSL is installed, you can use the SSL certificate checker to determine whether there are any potential security gaps which could endanger the data exchange. Over the last few years serious security leaks have been discovered repeatedly, particularly with older SSL versions and implementations. Use the SSL tester from IONOS to avoid potential gaps in your SSL certificate.
If you are having trouble installing your SSL certificate, then you can find solutions for various issues in this overview. Here, you can also find instructions on how to enable your SSL certificate for MyWebsite or Managed WordPress websites. Help for setting up an SSL certificate for web hosting packages and tips on how to apply an SSL certificate to root servers can also be found here. If you cannot find a suitable solution, then contact our expert support around the clock and they will be happy to help.
The SSL encryption protocol encrypts the exchange of data using a number of keys, which are authenticated through various digital certificates. The following process is the foundation for this and is completed within a matter of seconds:
- The dispatcher retrieves the public key of the recipient.
- A digital certificate proves the authenticity, scope of application and jurisdiction of the public recipient key.
- A digital signature verifies the certificate of the public recipient key.
- This signature can in turn be verified by the public key of the certificate issuer.
- The issuers key has to prove its validity with a certificate.
This process forms an SSL certificate chain that ensures that both dispatcher and recipient can rely on the authenticity of the certified key. This also means that unauthorised third parties cannot read the encrypted data.The SSL certificate chain can be found in the "certificate chain" section of the SSL test. Provided the SSL certificate of the tested website is functioning properly, the result of the test will show a multilevel chain with green checks next to the certificate symbols.