> ## 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.

# firstName / lastName

> Customer's name for identity resolution and destination matching.

Customer's name. Used for identity resolution and destination matching.

```javascript theme={null}
window._upstack('track', 'purchase', {
  firstName: 'Jane',
  lastName: 'Smith',
  email: 'jane.smith@example.com',
  transactionId: 'ORD-123',
  value: 149.99,
  currency: 'USD'
});
```

| Type   | Required | Events     |
| ------ | -------- | ---------- |
| string | No       | All events |

## Privacy

Names are normalized (lowercase, trimmed) and SHA-256 hashed before being sent to advertising destinations.

## Related Properties

<CardGroup cols={2}>
  <Card title="email" icon="envelope" href="/pixel/events/properties/email">
    Customer email — primary identifier.
  </Card>

  <Card title="phone" icon="phone" href="/pixel/events/properties/phone">
    Customer phone number.
  </Card>

  <Card title="Address Properties" icon="location-dot" href="/pixel/events/properties/address">
    Shipping and billing address fields.
  </Card>
</CardGroup>