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

# Reference IDs

> Attach your own identifier to a test taker so Neurapulse results can be matched back to a record in your platform.

A **Reference ID** is your own identifier attached to a test taker — for example an employee number, a badge number, a driver ID, or the subject ID from your Impirica platform. It lets you match a Neurapulse test taker (and their result) back to the right record in your own system.

The Reference ID is optional. If you only run tests inside Neurapulse, you do not need it. It becomes useful when you are linking results back to another system.

## Setting a Reference ID

You can set a Reference ID when you add a test taker, or edit it later.

<Steps>
  <Step title="Open the Add or Edit Test Taker form">
    From a project, add a new test taker or open an existing one to edit. The form includes a **Reference ID** field.
  </Step>

  <Step title="Enter your identifier">
    Type the identifier your own system uses for this person — for example `EMP-12345`.
  </Step>

  <Step title="Save">
    Save the test taker. The Reference ID is stored against that test taker's entry in the project.
  </Step>
</Steps>

## Setting Reference IDs in Bulk

When you import test takers from a CSV file, include a **`referenceid`** column. Each row's value is applied to that test taker. The column name is not case-sensitive, and `refId` is also accepted.

<Tip>
  Importing with a `referenceid` column is the fastest way to link a large group of people who already exist in your own system.
</Tip>

## Rules and Limits

* **Optional** — a test taker can have no Reference ID.
* **Up to 500 characters.**
* **Allowed characters:** letters, numbers, and `_ - . + @`.
* **Not unique** — Neurapulse does not stop two test takers from sharing the same Reference ID. Use values that are unique in your own system if you rely on them to match records.

## Where the Reference ID Appears

* On the **test taker row** within the project, beneath the test taker's contact details.
* In **test taker exports**.
* In **test completion emails**, shown as a `Ref:` label.
* In the **result your connected platform retrieves**, so it can match the result back to your record. See [Linking with the Impirica Platform](/docs/Integrations/linking-with-the-impirica-platform).

<Note>
  A Reference ID is treated as information you supplied about the person. If a test taker's data is erased, the Reference ID is cleared along with their other personal details.
</Note>