For developers
Email you can
wire into your app.
A REST API for lists, subscribers and campaigns. A transactional API for OTP codes and notifications. Webhooks from automations. Delivery through the provider you choose.
REST API · Transactional API · Webhooks · SMTP and providers
REST API
Lists, subscribers, campaigns and more, with JSON responses.
Transactional API
OTP and notification emails from templates, one call each.
Webhooks
Automations can call your endpoint at any step.
Transactional API
One call per email,
from a template.
POST to /utility/v1/send with a template key, a recipient and the variables for your {{placeholders}}. Authenticate with its own X-API-Key. Sends use a dedicated priority lane, separate from the campaign queue. See Transactional Email for the full reference.
Webhooks
Let automations
call your code.
Add a webhook action to an automation and Flashmail calls your endpoint when a subscriber reaches that step. Automations can also start from an API event your app sends. See Automation for every trigger and action.
What you get
The building blocks for email in your product.
JSON in, JSON out.
REST API
Base URL api.flashmail.id/api/v1, Bearer token or api_token parameter.
Subscriber endpoints
List, add, update and tag subscribers.
Campaign endpoints
Work with campaigns from your code.
Transactional API
Templates with {{variables}}, sent through a priority lane.
Webhooks
Called from automation steps.
Delivery providers
Pick the provider or SMTP server that sends your email.
Delivery
Choose how
your email is sent.
Supported delivery providers include Amazon SES, SendGrid, Mailgun, Elastic Email, SparkPost, Blastengine, generic SMTP and Gmail (OAuth). Verify your sending domain with SPF, DKIM and DMARC.
Getting started
Send your first email from code.
Get a key, create a template, make a request.
-
1
Get your keys
Copy the API token from Account → API, and your X-API-Key for transactional sends.
-
2
Create a template
Add a template key, subject and HTML body with {{variables}}.
-
3
Make a request
POST the template key, recipient and variables to send.
Common questions.
What does an API response look like?
Responses are JSON with a status, a message and a data field, for example {"status":1,"message":"Success","data":…}.
Do transactional emails wait behind campaigns?
No. Transactional sends go through a dedicated priority lane, separate from the campaign sending queue.
Is the transactional API on every plan?
Access to the Email Utility API depends on your plan. The REST API uses the token from Account → API.
Ship email features
without building a mail system.
Create a free account and get your API token.