> ## Documentation Index
> Fetch the complete documentation index at: https://launchdarkly-preview.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Experiment flags

> This topic explains how you can use experiment flags to test a hypothesis.

> For the complete documentation index, see [llms.txt](/llms.txt). For the full documentation snapshot, see [llms-full.txt](/llms-full.txt).

## Overview

This topic explains how you can use experiment flags to test a hypothesis. These flags help you validate the impact of features you roll out to your app or infrastructure.

## About experiment flags

Experiment flags are temporary flags. In the most common use case, you wrap an experiment flag around code for a new or improved feature that impacts end users. Experiment flags can be either boolean or multivariate, so that the experiment can test multiple values. You can pair flags with metrics to compare context or system behavior between two or more flag variations. To learn more, read [Experimentation](/home/experimentation).

## Create experiment flags

To create an experiment flag:

1. Click **Create** and choose **Flag**. The "Create flag" dialog appears.
2. Enter a unique, human-readable **Name**. A suggested key auto-populates from the name you enter, but you can customize it if you wish.
3. (Optional) Click **Edit key** to update the flag key. You'll use this key to reference the flag in your code.
4. (Optional) Enter a **Description** of the flag. A brief, human-readable description helps your account members understand what the flag is for.
5. (Optional) Click **No template** and select **Experiment**. The flag type updates to **String**.
6. (Optional) Click **+** to add additional variations.
7. (Optional) Change the [default on](/home/flags/default-rule) and [default off](/home/flags/off-variation) variations if needed.
8. (Optional) Click on your member name to change the flag maintainer.
9. (Optional) Click the **tag** icon to add one or more [tags](/home/account/tags).
10. (Optional) Click on the views icon to add the flag to a [view](/home/account/views).
11. (Optional) Click **All SDKs** to make the flag [unavailable to client-side or mobile SDKs](/home/flags/flag-settings). Flags are available to all SDKs by default.
12. (Optional) Click **Temporary** to change the flag from [temporary to permanent](/home/flags/flag-settings).
13. Click **Create flag**.

The flag **Targeting** tab appears.

After you create a flag, you can make further changes to it as needed, such as to [update flag targeting](/home/flags/target).

To learn more, read [Creating new flags](/home/flags/new).

Then, run experiments on the flag. To get started, click **Add experiment** the flag's right sidebar. To learn more, read [Creating experiments](/home/experimentation/create).

## Modify the experiment flag template

To modify your experiment flag template:

1. Click the project dropdown. The project menu appears:

<Frame caption="The project menu.">
  ![The project menu.](https://files.buildwithfern.com/https://launchdarkly.docs.buildwithfern.com/docs/b0dbb7934c69e875ae14bdb12a880ae2b7d28030b397db14e553fe9709d74fcc/assets/images/auto/project-menu-dropdown.auto.png)
</Frame>

2. Select **Project settings**.
3. Select **Flags**. The **Flags** settings list appears.
4. In the "Flag templates section, click the **pencil** icon next to "Experiment."
5. In the "Tags" section, type to add tags to each new flag by default.
6. Click **Save**.

Verify that the updated default template settings are correct by navigating to the **Flags** list and creating a new experiment flag.