Home : Software Terms : Activation Key Definition

Activation Key

A software activation key is a string of letters and/or numbers used to register or activate a software application. You may receive an activation key when you purchase a commercial software program.

The purpose of an activation key is to prevent software piracy by ensuring only users who have purchased a program can use it. Some software programs will not function without a valid activation key, while other programs will run in "trial mode" or with restricted functionality. Registering or activating the software with the activation key removes these limitations.

There is no standard activation key format, but most include both letters and numbers. They often contain groups of characters separated by dashes for readability. Most license keys contain at least 10 characters, and some may have over 30. Below is an example of a typical activation key:


Developers can implement software activation keys in several different ways. The most basic method is to simply check a key against a database or list of keys. If a user enters an activation key that matches one in the list, the software is successfully activated. A more advanced method is to generate activation keys dynamically based on a user's registration information (such as an email address). An algorithm in the program can then check the key to see if it corresponds with the email address used to register the software program. Modern software programs often use online activation, which verifies the key on a remote server. This allows the developer to limit the number of uses for each key and revoke keys if necessary.

Software activation keys may be found inside retail software boxes or order confirmation emails. You can typically open the activation window in a software program by locating the "Activate" or "Register" option in the program.

NOTE: An activation key may also be called a product key, software key, license key, registration code, or serial number.

Updated: March 1, 2018

Cite this definition:


TechTerms - The Tech Terms Computer Dictionary

This page contains a technical definition of Activation Key. It explains in computing terminology what Activation Key means and is one of many software terms in the TechTerms dictionary.

All definitions on the TechTerms website are written to be technically accurate but also easy to understand. If you find this Activation Key definition to be helpful, you can reference it using the citation links above. If you think a term should be updated or added to the TechTerms dictionary, please email TechTerms!

Subscribe to the TechTerms Newsletter to get featured terms and quizzes right in your inbox. You can choose to receive either a daily or weekly email.

Sign up for the free TechTerms Newsletter

How often would you like to receive an email?

You can unsubscribe at any time.
Questions? Please contact us.