Introduction

The DirectIQ API is a RESTful interface to the DirectIQ email marketing platform. It lets you automate contact management, campaigns and transactional email from your own systems.

At a glance


Base URL	`https://api.directiq.com`
Protocol	HTTPS only
Format	JSON (UTF-8) for requests and responses
Authentication	`X-API-Key` header (recommended) or HTTP Basic. See Authentication
Current version	`v2`, in the URL path. See Versioning
Rate limit	500 requests per minute per account

Make your first request

Copy your X-API-Key from the API Keys page and run:

curl https://api.directiq.com/v2/senders \
  -H "X-API-Key: YOUR_X_API_KEY"

{
  "data": [
    {
      "id": 1042,
      "name": "Jane from Acme",
      "email": "[email protected]",
      "reply_to": "[email protected]",
      "is_default": true,
      "status": "confirmed",
      "created_at": "2026-09-14T08:21:37Z"
    }
  ],
  "has_more": false,
  "next_page_token": null
}

Requests

Send every request over HTTPS.
Send request bodies as JSON with Content-Type: application/json.
v2 field names, query parameters and error codes use snake_case.
Timestamps are ISO 8601 in UTC, such as 2026-11-04T09:30:00Z.

Responses

Status	Meaning
`200 OK`	The request succeeded.
`201 Created`	The resource was created. Its URL is in the `Location` header.
`204 No Content`	The request succeeded and there is nothing to return, for example after a delete.
`400 Bad Request`	The request is malformed or a field is invalid.
`401 Unauthorized`	The credentials are missing or wrong.
`403 Forbidden`	The credentials are valid, but the account cannot perform this action.
`404 Not Found`	The resource does not exist, or it belongs to another account.
`409 Conflict`	The request conflicts with the resource's current state.
`410 Gone`	The endpoint has been retired. See Versioning.
`422 Unprocessable Entity`	The request is valid, but a business rule rejected it, for example an unconfirmed sender.
`429 Too Many Requests`	You exceeded the rate limit.
`5xx`	Something went wrong on our side. Retry with backoff.

Errors

v2 errors use the Problem Details format (application/problem+json):

{
  "type": "https://docs.directiq.com/errors/validation_failed",
  "title": "Validation failed",
  "status": 400,
  "detail": "One or more fields are invalid.",
  "code": "validation_failed",
  "request_id": "1-6728a1f3-3c9e0b7d2a4f5e6b7c8d9e0f",
  "errors": {
    "email": ["Must be a valid email address."]
  }
}

Use code in your error handling. It is stable; title and detail are written for people and may change.
errors appears only on validation errors. It maps each field name to its messages.
Every response includes an X-Request-Id header. Quote it, or request_id, when you contact support.

Pagination

List endpoints return results a page at a time:

curl "https://api.directiq.com/v2/senders?limit=50" \
  -H "X-API-Key: YOUR_X_API_KEY"

limit sets the page size. It accepts 1 to 100 and defaults to 25.
When has_more is true, request the next page with page_token set to the next_page_token value from the previous response. Keep every other parameter the same.

Rate limits

Each account can make 500 requests per minute. Every response reports where you stand:

X-RateLimit-Limit: 500
X-RateLimit-Remaining: 497
X-RateLimit-Reset: 1793750460

X-RateLimit-Reset is the Unix time (in seconds) when the current window ends.

When you reach the limit, the API returns 429 Too Many Requests with a Retry-After header that gives the number of seconds to wait. Wait that long before you retry. Clients that keep sending requests after a 429 can have their IP address blocked for a while.

Next steps

Authentication: choose how to send your credentials.
Versioning: how versions work and how endpoints are retired.

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