# Parameter Settings

### What are Parameter Settings?

When implementing the changes for each group in an A/B Test, you can flexibly apply items such as text, URLs, and numbers as parameters.

Complex items can be managed using JSON.\
When a value configured as a parameter needs to be updated later, you only need to change it in the Dashboard and it is immediately reflected in your service.

### Configure Parameters

1. Parameter settings can be configured and modified when the A/B Test in the \[Production Environment] is in Draft status. Once started, they cannot be modified.\
   a. If you need to modify parameters after the test has started, create a new version of the A/B Test or create a new A/B Test.
2. Parameter settings can be configured separately for the \[Production Environment] and \[Development Environment].

![2396](/files/HT7Qfn3n5zN3wZsUn4mp)

**1. Parameter Key**\
Enter the parameter key configured in the code in this field. The parameter key is a required field. Key values can only contain letters, numbers, \_, -, and . and must be between 1 and 128 characters. Duplicate parameter keys within a single A/B Test are not allowed.

**2. Parameter Type**\
Use the parameter type to set what format the parameter value will be in. The content you can enter in the parameter value varies by type.

* String
* Number
* Boolean
* JSON

**3. Parameter Value**\
You can set the desired value for each group. The configured settings are not reflected for users until the A/B Test starts.

**4. Add Parameter**\
You can add up to 10 parameter configurations.

### How to Configure Parameters

1. Visit the A/B Test detail page, create parameter keys for the items you want to manage as parameters, and select the appropriate type.
2. Enter the content to apply to the parameter for each group in the parameter value.
3. Enter the parameter key in the code for each group, implement and deploy it so that the corresponding parameter value for each group is fetched.
4. Register test devices and verify that the parameter key/value is being served correctly for each desired group.
5. If the items configured as parameters are working correctly, you are ready to start the A/B Test.


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