A digital certificate is a type of electronic document that verifies the identity of the owner of a public key and is often used to secure online transactions and communications.

What is digital certificates?

Digital certificate is an electronic document used to verify the identity of a person, company, or device during digital communication. It contains information about the certificate holder (e.g., organization name), a public encryption key, and a digital signature from a trusted certificate authority (CA). Digital certificates are essential for securing websites (HTTPS), digitally signing documents, and authenticating email communication or devices.

How digital certificates is used in practice

Examples of common use cases:

• The e-shop’s website has a certificate that confirms its authenticity and enables encrypted connections (https://).
• Employees sign contracts using an electronic signature – verified using a digital certificate.
• Company emails are signed and encrypted, allowing the recipient to verify who sent the message and that it hasn’t been altered.
• Internal systems communicate via secure channels whose trustworthiness is verified by a certificate.
• When connecting to the company VPN, a certificate is used to verify the identity of the device.

These examples show that certificates are not just about encryption—they’re about trust. They confirm that you're communicating with the party you expect to.

Digital certificate vs. related terms – What’s the difference?

• Digital certificate vs. electronic signature
  An electronic signature is the result of signing a document. The digital certificate is the tool that verifies who signed it.
• • Digital certificate vs. public key
  A public key is part of the certificate. But a certificate also includes identity data and verification from a trusted CA.
• Digital certificate vs. HTTPS
  HTTPS uses a digital certificate to allow browsers to verify the identity of the website and ensure an encrypted connection.

Understanding these distinctions helps organizations choose the right tools for secure communication and digital identity verification.

How to manage digital certificates in your company

Recommended steps:

• Inventory all systems using digital certificates—websites, VPNs, emails, internal tools.
• Use certificates from trusted CAs, such as Let’s Encrypt, DigiCert, or PostSignum.
• Monitor certificate expiration dates and set alerts to renew them in time.
• Regularly update and manage certificates, including revoking any that are expired or compromised.
• Train employees on how to use digital signatures and verify certificates.
• Consider running an internal CA if you operate many internal services or devices.

Digital certificates are foundational to modern cybersecurity—but only if well managed. A missed renewal can cause website outages or lost customer trust. Proper certificate hygiene is a basic but critical part of any company’s security posture.