Use the Attribution API to send attribution campaign events from your mobile measurement partner or marketing platform to Amplitude. Each event identifies a user with an `idfa`, `idfv`, `adid`, or `android_app_set_id` so Amplitude can match the attribution data to the correct user and surface it across your analyses. ## Regions The base URL depends on your project's data residency. In all examples on this page, use the default base URL unless your project uses Amplitude's EU data center—in that case use the EU base URL in this table. This API uses `api.amplitude.com` (default) or `api.eu.amplitude.com` (EU). Event ingestion often uses `api2.amplitude.com`; other Amplitude APIs use `core.amplitude.com`, `data-api.amplitude.com`, or `experiment.amplitude.com` as documented for each product. The `https://analytics.amplitude.com` hostname is the Analytics web app (browser UI), not this API endpoint. | Data residency | Base URL | | -------------- | ------------------------------ | | Default | `https://api.amplitude.com` | | EU | `https://api.eu.amplitude.com` | ## Matching and identifier requirements - When Amplitude can't match an attribution event to an existing user, Amplitude holds the event for up to 72 hours. If no event is logged for a matching user within 72 hours, Amplitude drops the attribution data. - For most Amplitude partners, Amplitude uses Advertising ID (IDFA or ADID) or vendor ID (IDFV or App Set ID) to attribute users and events. Send these identifiers in attribution requests, and set the `idfa`, `idfv`, `adid`, and `android_app_set_id` fields in Amplitude as the Attribution ID. - If you use the iOS SDK or Android SDK, enable Advertising ID tracking by following the [iOS Swift SDK instructions](/docs/sdks/analytics/ios/ios-swift-sdk#advertiser-id). The JavaScript SDK and React Native SDK can't collect Advertising ID automatically because of Google's and Apple's privacy rules for advertising ID and web tracking. Send the Advertising ID through the HTTP API endpoint so Amplitude can match attribution events. Refer to the keys in the [HTTP API V2](/docs/apis/analytics/http-v2) doc. ## Send an attribution event Send a `POST` request to {{standard_endpoint}} with two arguments: `api_key` and `event`. ### Required arguments | Name | Description | Example | | --------- | --------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `api_key` | Required. The project's API key. | `api_key` | | `event` | Required. A request parameter representing the event, in JSON format. | `{"event_type":"[YOUR COMPANY] Install", "idfa": "AEBE52E7-03EE-455A-B3C4-E57283966239", "user_properties": {"[YOUR COMPANY] media source": "facebook", "[YOUR COMPANY] campaign": "refer-a-friend"}, "platform": "ios"}` | ### Event argument keys | Key | Description | Example | | ------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------- | | `event_type` | Required. String. The event info. Prefix with brackets `[YOUR COMPANY]`. | `[YOUR COMPANY] Install` | | `platform` | Required. String. Either `ios` or `android`. | `ios` | | `idfa` or `idfv` | Required for iOS. String. The Identifier for Advertiser or the Identifier for Vendor. Include at least one for iOS devices. | AEBE52E7-03EE-455A-B3C4-E57283966239 | | `adid` or `android_app_set_id` | Required for Android. String. The Google ADID or App Set ID, or Amazon Advertising ID for Amazon devices. Include at least one for Android devices. | AEBE52E7-03EE-455A-B3C4-E57283966239 | | `android_id` | Optional. String. (Android) The Android ID | AEBE52E7-03EE-455A-B3C4-E57283966239 | | `android_app_set_id` | Optional. String. (Android) The Android App Set ID | AEBE52E7-03EE-455A-B3C4-E57283966239 | | `user_properties` | Optional. Dictionary. A dictionary of attribution properties prefixed with brackets `[YOUR COMPANY]`. | `{"[YOUR COMPANY] media source": "Facebook"}` | | `time` | Optional. Long. Timestamp of the event in milliseconds since epoch. | 1396381378123. Defaults to the upload time. | ### Example request The following code shows attribution for iOS. {% code-group %} ```curl cURL curl --location --request POST 'https://api.amplitude.com/attribution' \ --data-urlencode 'api_key=123456789' \ --data-urlencode 'event={"event_type":"[YOUR COMPANY] Install", "idfa": "AEBE52E7-03EE-455A-B3C4-E57283966239", "user_properties": {"[YOUR COMPANY] media source": "facebook", "[YOUR COMPANY] campaign": "refer-a-friend"}, "platform": "ios"}' ``` ```bash HTTP POST /attribution HTTP/1.1 Host: api.amplitude.com Content-Length: 365 api_key={{api_key}}&event=%7B%22event_type%22%3A%22%5BYOUR%20COMPANY%5D%20Install%22%2C%20%22idfa%22%3A%20%22AEBE52E7-03EE-455A-B3C4-E57283966239%22%2C%20%22user_properties%22%3A%20%7B%22%5BYOUR%20COMPANY%5D%20media%20source%22%3A%20%22facebook%22%2C%20%22%5BYOUR%20COMPANY%5D%20campaign%22%3A%20%22refer-a-friend%22%7D%2C%20%22platform%22%3A%20%22ios%22%7D ``` {% /code-group %} The following code shows attribution for Android. {% code-group %} ```curl cURL curl --location -g --request POST 'https://api2.amplitude.com/attribution?api_key=123456789&event={"event_type":"[YOUR COMPANY] Install","adid": "AEBE52E7-03EE-455A-B3C4-E57283966239", "user_properties": {"[YOUR COMPANY] media source": "facebook", "[YOUR COMPANY] campaign": "refer-a-friend"}, "platform": "android"}' ``` ```bash HTTP POST /attribution?api_key=api_key&event="{event_type":"[YOUR COMPANY] Install","adid": "AEBE52E7-03EE-455A-B3C4-E57283966239", "user_properties": {"[YOUR COMPANY] media source": "facebook", "[YOUR COMPANY] campaign": "refer-a-friend"}, "platform": "android"} HTTP/1.1 Host: api2.amplitude.com ``` {% /code-group %} ## Responses | Code | Message | | ---- | ------------------------------------------- | | 200 | Success | | 400 | The expected JSON is formatted incorrectly. |