How to Use Counter in JMeter

This article talks about using the Counter element in a performance test script.

Maharshi Shah

Sep. 23, 16 · Tutorial

40.2K Views

From sending an email to load testing database, JMeter allows us to create some really sophisticated load testing scenarios. It provides a range of different elements to accomplish our performance testing goals. Counter is one such JMeter element which can prove immensely useful for testers. In this article, we will see how we can use JMeter Counter in our performance test script.

For easier understanding here, we will take an example of test data generation using JMeter. In that, we will register multiple users by incrementing a username (Eg. user+1, user+2, user+3 and so on). This is a very simple example of test data creation which testers often have to carry out. And it can be automated using JMeter Counter. So, without wasting any more time, let’s see how we can do this.

Using JMeter Counter:

The screenshot below shows parameters for an HTTP request. Since we will be sending our request in JSON format, we have selected Body Data option here.

HTTP Request

We will change ‘username’ value in the above request to ‘user+1’, ‘user+2’ etc for multiple user creation. This is where JMeter Counter comes into the picture. It allows us to increment a value by some number. To add JMeter Counter in the script, right click Thread Group and select Add–>Config Element–>Counter option.

The screenshot below shows options present in Counter element. Since we are starting from value 1 and incrementing it by 1, we have set Start and Increment values by 1 respectively. Reference Name value is set to ‘userCount’ which we will use in our JSON request.

JMeter Counter Options

Since we have our counter setup now, we just need to update our JSON request with a counter reference name (userCount in our case). The screenshot below shows how we can do it.

Updated HTTP Request

Now that we have our setup ready, we can run our script for multiple users and get our users created with sequential numbers.

While this example of JMeter Counter shows test data creation, it can come in handy for other testing activities also. We encourage you to try it out in your project and share your feedback in comments.

Test data

Published at DZone with permission of Maharshi Shah. See the original article here.

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