Quickstart

Get a mailer URL and an API keyCopy Anchor Link

Flaresend runs in your own Cloudflare account, so you need three things before you send:

1. A deployed mailer Worker. Its URL is your base URL, for example https://mailer.example.com. If you don't have one yet, follow Deploy.
2. A project with at least one allowed sending domain, for example acme.com.
3. An API key for that project. Keys start with fs_live_ (sends for real) or fs_test_ (records the email, never sends).

Create the key in the dashboard under API Keys → Create API key, or with the CLI:

flaresend keys create --project acme --name quickstart --mode live

The full key is shown once. Store it as an environment variable:

FLARESEND_API_KEY=fs_live_...

See API keys for how keys are stored and revoked.

Install the clientCopy Anchor Link

npm install @flaresend/client

The only runtime dependency is @flaresend/types. It needs a global fetch, so Node 18 or later.

Send an emailCopy Anchor Link

import { Flaresend } from '@flaresend/client';

const flaresend = new Flaresend({
  apiKey: process.env.FLARESEND_API_KEY!,
  baseUrl: 'https://mailer.example.com',
});

const { id, status } = await flaresend.emails.send({
  from: 'Acme <hello@acme.com>',
  to: 'ada@example.com',
  subject: 'Hello from Flaresend',
  html: '<p>It works.</p>',
  text: 'It works.',
});

console.log(id, status); // email_01K6B2Y4ZP9R3M7T8V5N2QXW4C queued

from must be an address on one of the project's allowed domains. If the project has a default sender, you can leave from out.

The call returns as soon as the email is stored and queued. It does not wait for Cloudflare to deliver it. baseUrl has no default: always pass your own mailer URL.

Check the statusCopy Anchor Link

Fetch the email to see where it is:

const email = await flaresend.emails.get(id);

console.log(email.status); // queued → sending → sent → delivered
for (const r of email.recipients) console.log(r.address, r.status);
for (const e of email.events) console.log(e.createdAt, e.type);

The same email is on the dashboard's Emails page, with its recipients, its event timeline and the rendered body.

sent means Cloudflare accepted the message. delivered comes later, when Cloudflare reports that the receiving server took it. See Email statuses for every status.

Next stepsCopy Anchor Link