> ## Documentation Index
> Fetch the complete documentation index at: https://docs.upstackdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Trial Started: Track Free Trial Initiations

> Track the total number of trial start events. Monitor product-led growth and self-serve acquisition.

<Tip>
  Trial Started measures the total number of times users started a free trial, tracked by the Upstack pixel.
</Tip>

## Formula

<Info>
  **Trial Started** = **COUNT** ( Events ) **WHERE** event\_type = trial\_started
</Info>

### Formula Components

| Metric                           | Definition                                |
| -------------------------------- | ----------------------------------------- |
| **Events**                       | All tracked events from the Upstack pixel |
| **event\_type = trial\_started** | Filters to only trial start events        |

| Metadata        |                         |
| --------------- | ----------------------- |
| **Type**        | Number                  |
| **Data Source** | [Upstack Pixel](/pixel) |
| **Aggregation** | Count                   |

***

## Example

Your SaaS company tracked trial starts by acquisition source this month.

| Source    | Trial Started | Trial Activated | Converted to Paid |
| --------- | ------------- | --------------- | ----------------- |
| Organic   | 450           | 320             | 95                |
| Paid Ads  | 380           | 260             | 75                |
| Referral  | 120           | 100             | 42                |
| Partner   | 80            | 65              | 28                |
| **Total** | **1,030**     | **745**         | **240**           |

***

## How It Works

This metric counts all trial started events tracked by the Upstack pixel. A trial started event fires when a user begins their free trial period. This is a key PLG (product-led growth) metric that indicates acquisition success and feeds the trial-to-paid conversion funnel.

***

## When to Use

| Scenario            | Action                             |
| ------------------- | ---------------------------------- |
| PLG acquisition     | Track product-led user acquisition |
| Funnel analysis     | Measure trial funnel top           |
| Growth planning     | Set trial start targets            |
| Channel attribution | Track trials by acquisition source |

***

## Related Metrics

| Metric                                                                                 | Relationship                    |
| -------------------------------------------------------------------------------------- | ------------------------------- |
| [Trial Activated](/reference/metrics/funnel/conversions/trial-activated)               | Users who activate during trial |
| [Trial Converted](/reference/metrics/funnel/conversions/trial-converted)               | Trials converted to paid        |
| [Cost per Trial Started](/reference/metrics/funnel/conversions/cost-per-trial-started) | Acquisition cost                |

[See all Conversions metrics →](/reference/metrics/funnel/conversions)