Quickstart

From a signup form on your site to a confirmed subscriber, in about five minutes.

This walks the whole loop: a form on your site, a confirmation email, a confirmed subscriber you can send to.

1. Create a topic

In the dashboard, under Audience → Topics, create one. Call it something a recipient would recognise, because they will see the name on the unsubscribe page: “Weekly newsletter” rather than “list-2”.

Note its id. It looks like tp_7xk2m9qv4w.

2. Get a publishable key

Settings → API keys. Create a key and pick publishable.

Publishable keys are safe in front-end code. They can do exactly one thing — subscribe somebody to a topic — and nothing else. Secret keys, which can read and change your audience, must never leave your server.

Start with a test key. Test keys validate everything and send nothing, so you can get your form working without mailing anyone. More on that in test and live keys.

3. Post a signup

curl https://api.zevcampaign.com/v1/subscribe \
  -H "Authorization: Bearer pk_test_your_key_here" \
  -H "Content-Type: application/json" \
  -d '{
    "topic_id": "tp_7xk2m9qv4w",
    "email": "ada@example.com",
    "first_name": "Ada"
  }'

{
  "data": {
    "status": "confirmation_sent"
  }
}

From a browser, the same call with fetch:

await fetch('https://api.zevcampaign.com/v1/subscribe', {
  method: 'POST',
  headers: {
    Authorization: 'Bearer pk_live_your_key_here',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    topic_id: 'tp_7xk2m9qv4w',
    email: form.email.value,
    first_name: form.firstName.value,
  }),
});

4. Expect one of two answers

status is either confirmation_sent or subscribed, and that is all you get.

It is deliberately this coarse. The response is identical whether the address was new, already subscribed, still pending, or previously unsubscribed. Anything more specific would turn your public form into a way for anyone to check whether a particular person is on your list, which is their business and not something we will leak on your behalf.

Show the same friendly message either way: “Check your inbox to confirm.”

5. They confirm

On a double opt-in topic, which is the default, we email the address a confirmation link from your brand, not from us. Someone who typed their address into your bakery’s newsletter box expects to hear from the bakery.

When they click it, the subscription becomes active and your contact.subscribed webhook fires. That event always means real consent, which is why it is worth wiring up: your own CRM can trust it without re-checking.

6. Send

Build the campaign in the dashboard and send it to the topic.

If you are on a trial, or your brand has not been reviewed yet, you can only send to addresses you have verified as your own. That is not a bug and it is not a quota: see getting approved for what lifts it and how long it takes.

What next

• Consent and double opt-in — what we record, and why
• Webhooks — so your systems hear about this too
• Contacts API — importing an audience you already have

Updated at, Saturday, October 10, 2026