# Save profile > Creates or updates a profile in Adapty Mail. A profile carries the user's email and attributes > that Adapty Mail uses to identify recipients and build [segments](/docs/mail-segments). > > Identify each user by a stable `external_profile_id`. Sending the same `external_profile_id` > again updates the existing profile rather than creating a duplicate. ## OpenAPI ```yaml /api-specs/adapty-mail-api.yaml post /api/v1/profile/save/ openapi: 3.1.0 info: title: Adapty Mail API version: 1.0.0 description: | The Adapty Mail API lets you send user profiles and transaction events to Adapty Mail directly from your server, without routing the data through the Adapty SDK. Use it to: - Add subscribers when you don't have a base in Adapty Mail yet. - Reuse the subscriber base from your other apps. - Feed Adapty Mail server-to-server, with your backend as the source of truth. A profile with an email is enough for the **never purchased** flow. Every other flow (renewal cancelled, billing issue, expired, refunded) is driven by purchase history, so those profiles also need transaction events to be placed in the right flow. For a step-by-step walkthrough, see [Send emails and transactions via the Adapty Mail API](/docs/mail-send-data-via-api). servers: - url: https://api-mail.adapty.io description: Production server paths: /api/v1/profile/save/: post: summary: Save profile description: | Creates or updates a profile in Adapty Mail. A profile carries the user's email and attributes that Adapty Mail uses to identify recipients and build [segments](/docs/mail-segments). Identify each user by a stable `external_profile_id`. Sending the same `external_profile_id` again updates the existing profile rather than creating a duplicate. operationId: saveProfile security: - apikeyAuth: [] requestBody: required: true content: application/json: schema: $ref: "#/components/schemas/ProfileDTO" examples: basic: summary: Profile with an email, ready for the "never purchased" flow value: external_profile_id: user_12345 external_created_at: "2026-06-01T10:30:00Z" email: jane@example.com country: US custom_attributes: plan: trial responses: "200": description: Profile saved successfully. The response body is an empty object. content: application/json: schema: type: object examples: default: value: {} "400": description: Validation failed — a required field is missing or invalid. `field_name` shows which field. content: application/json: schema: $ref: "#/components/schemas/Errors" examples: default: value: errors: - message: Field required error_code: base_error status_code: 400 field_name: email "403": description: Missing or invalid secret API key. content: application/json: schema: $ref: "#/components/schemas/Errors" examples: default: value: errors: - message: Secret key doesn't exist error_code: secret_key_does_not_exist_error status_code: 403 field_name: null components: schemas: ProfileDTO: type: object required: - external_profile_id - external_created_at - email properties: external_profile_id: type: string description: | Stable identifier for the user, owned by your app or backend. Reuse the same value across requests so Adapty Mail links emails, clicks, and purchases to one profile. Never use an anonymous or per-install identifier. external_created_at: type: string format: date-time description: | The user creation time, in ISO 8601 format (for example, `"2026-06-01T10:30:00Z"`). You can use this date in segments. email: type: string format: email description: The user's email address. Adapty Mail delivers campaigns to this address. first_name: type: string description: The user's first name. last_name: type: string description: The user's last name. gender: type: string description: The user's gender. birthday: type: string format: date description: The user's date of birth, in ISO 8601 format (for example, `"1990-05-21"`). country: type: string description: The user's country as a two-letter uppercase ISO 3166-1 alpha-2 code (for example, `US`). store_country: type: string description: The user's store region as a two-letter uppercase ISO 3166-1 alpha-2 code (for example, `US`). custom_attributes: type: object description: | Arbitrary key-value pairs (string or number values) to attach to the profile. Use them to build [segments](/docs/mail-segments) — for example, `plan`, `signup_source`, or `trial_days`. device_info: $ref: "#/components/schemas/DeviceInfoDTO" Errors: type: object description: Standard error response. Every failure returns a 4XX status with this shape. properties: errors: type: array items: type: object properties: message: type: string description: Human-readable description of the error. error_code: type: string description: Machine-readable error identifier. status_code: type: integer description: HTTP status code for this error. field_name: type: string description: The request field that caused the error, or `null` if the error isn't field-specific. DeviceInfoDTO: type: object required: - platform properties: platform: type: string description: The platform the user is on, for example, `iOS` or `Android`. device: type: string description: Device model, for example, `iPhone15,2`. os: type: string description: Operating system version, for example, `17.5`. locale: type: string description: The user's locale, for example, `en-US`. timezone: type: string description: The user's timezone, for example, `America/New_York`. app_version: type: string description: Version of your app the user is running, for example, `3.1.0`. securitySchemes: apikeyAuth: type: apiKey in: header name: Authorization description: | Authenticate every request with your Adapty Mail secret API key, sent as the **Authorization** header with the value `Bearer {your_secret_api_key}`, for example, `Bearer secret_live_...`. Find this key in Adapty Mail under **Settings**. The key is project-specific — it identifies the project the data belongs to, so the profile and transaction endpoints don't take a project ID. ```