This document contains the necessary information to use the GMetrix LTI endpoint, including URLs, parameters, and use cases. This document assumes basic knowledge of the LTI 1.1 specification. More information on LTI 1.1 can be found here:

Tool URL


The consumer key is directly tied to the testing center on the GMetrix side. This means that each testing center in the GMetrix system that needs access to the LTI will need their own consumer key/secret.

For instructions on generating your Key and Secret please click on this link, How-to Create Your Key and Secret


HMAC-SHA1, HMAC-SHA256, and HMAC-SHA512 are supported.


In addition to parameters for OAuth and student account information, GMetrix uses optional custom parameters to tell the tool the desired functionality. If none are sent, the student will simply be logged in to the GMetrix panel and have full access to the GMetrix site. This is a Single Sign On only implementation.

gmxresourcekey -  A Unique key used to directly link to a GMetrix resource. These resource keys can be found at on the home page in the LTI section. 

If a resource key is sent, GMetrix panel will be in limited mode, and the student will only have access to the resource that matches the key. 

  • accesscode - A custom parameter containing the GMetrix access code that will be used to access the content on the GMetrix site. This access code will be associated to the student's account, and will be the access code used by default to access the resource if a resource is included. 

  • If no access code is included, the student will need to redeem an access code that grants access to the requested resource in order to access the resource.

customerId - If included, the student will be associated with the partner with this customerId for reporting purposes.


GMetrix implements the Basic Outcomes Service defined in the LTI specification. If an Outcome Service URL is included with the GMetrix Resource Key, the score will be returned to the outcome URL once the resource has been completed. The sourcedid parameter is used to link the GMetrix resource to the LTI resource in your LMS.  Scores are sent as a percentage, using a decimal between 0.00 and 1.00. If no GMetrix Resource key is included, the outcomes URL will not be called.


If the student saves a test in the GMetrix system, they will be returned to your LMS using the

launch_presentation_return_url. This will leave the test in progress and will not call the outcomes url. The test will resume if the same launch link is clicked. A new attempt of the test can only be launched after the student has finished the previous attempt.


If you are using one of the following LMS platforms, we have created additional documentation for the following: