> For the complete documentation index, see [llms.txt](https://docs.sprinthub.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sprinthub.com/en/topics/api/api-how-to-relate-a-custom-object-to-a-contact.md).

# API - How to Relate a Custom Object to a Contact

### Route

<mark style="color:green;">`POST`</mark> `/customobjects/link?apitoken=your-token&i=your-instance`

### Query Params

<table><thead><tr><th width="291">Key</th><th width="450">Description</th></tr></thead><tbody><tr><td>i</td><td>Identifier of your instance, subdomain.</td></tr><tr><td>apitoken</td><td>API token.</td></tr></tbody></table>

### Body

<table><thead><tr><th width="291">Key</th><th width="450">Description</th></tr></thead><tbody><tr><td>objectId</td><td>ID of the created Object. If it was created via API, it is returned by <a href="/pages/ca8a1838330311bd80c9d1104159be1c08be1267">this call</a>.</td></tr><tr><td>linkType</td><td>Must be <code>"lead"</code>.</td></tr><tr><td>targetId</td><td>ID of the contact within Sprinthub that will be related to the Custom Object.</td></tr><tr><td>amount</td><td>Must be <code>1</code>.</td></tr></tbody></table>

## Testing Custom Object Relationship

The request was sent using the software *Postman*. The expected response is an object representing the relationship between the Object and the lead.

<div data-with-frame="true"><figure><img src="/files/91c6d97370c836b0b4dc9112f448ae130f903d01" alt=""><figcaption><p><em>Request to relate a Custom Object to a contact.</em></p></figcaption></figure></div>

### Checking in the Lead's Full Data

When relating a Custom Object to a contact, it should appear as in the image below.

<div data-with-frame="true"><figure><img src="/files/2db75d09e19c01cb574a790475afebde3e4682db" alt=""><figcaption><p><em>Custom Object tab within the contact.</em></p></figcaption></figure></div>


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