LettrLabs API

Attributions and Conversions

Record conversions against the mail you send and read them back for reporting.

Conversions let you tell LettrLabs when a recipient took action after receiving your mail — a purchase, a signup, a booked appointment — so you can attribute outcomes to a campaign and measure return on your direct mail.

Record conversions

Send one or more conversions in a single call to POST /v1/conversions. The exact body — what identifies a recipient, the conversion value, and any metadata — is documented on the POST /v1/conversions reference page, with a live console.

curl -X POST https://app.lettrlabs.com/api/v1/conversions \
  -H "X-API-KEY: your_api_key_here" \
  -H "Content-Type: application/json" \
  -d '[ { /* see the reference for the conversion shape */ } ]'

Read conversions back

ActionEndpoint
List all conversionsGET /v1/conversions
Check one conversion's statusGET /v1/conversions/{id}/status
Delete conversionsDELETE /v1/conversions/{id}

Each is documented in full, with parameters and response schemas, under API Reference.

How attribution fits together

  1. You send mail with an order.
  2. A recipient acts — and your system calls POST /v1/conversions to record it.
  3. You read conversions back for reporting, or check an individual conversion's processing status.

For richer recipient‑level reporting, see the Order Recipient Analytics group in the API Reference.

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