FeaturesWebhooks
Know what happened after you hit send.
Receive email delivery events in your application so you can update records, investigate failures, and respond to bounces as they happen.
Webhook deliveries
Signed JSON POST
POST https://example.com/webhooks/prontuno
- email.delivered ada@example.com 200 09:14:05
- email.sent grace@example.com 200 09:14:04
- email.bounced alan@example.org 200 09:14:02
- email.deferred mary@example.net 503 · retrying 09:13:58
- email.delivered linus@example.com 200 09:13:51
Why it matters
Turn delivery signals into action
Instead of polling for the status of each email, your application is told when something changes, so records stay current and failures surface quickly.
- Only the events you need
- Each endpoint subscribes only to the events it acts on, so every system receives just what it needs.
- Scope each endpoint
- Receive events for your whole team, or only for one verified sending domain.
- Manage by API or dashboard
- Create, update, and delete endpoints and rotate signing secrets through the API or your Prontuno account.
The details
Events you can trust, processed once
An endpoint on the public internet can receive forged, repeated, or missed requests. Signatures, event IDs, and retries address each of these.
| Event | Sent when |
|---|---|
| email.sent | Prontuno accepted the message and passed it to its mail servers. |
| email.delivered | The recipient’s mail server accepted the message. |
| email.deferred | The receiving server asked for a later retry. Prontuno retries automatically. |
| email.bounced | The receiving server refused the message. |
| email.rejected | Prontuno did not send the message, for example because the recipient is on the suppression list. |
| email.expired | Delivery kept being retried until the retry period ran out without success. |
| email.complained | The recipient reported the message as spam to their mailbox provider. Prontuno suppresses the address automatically. |
- HMAC-SHA256 signatures
- The Prontuno-Signature header is computed from the timestamp and raw body with your endpoint secret. A request without a valid signature did not come from Prontuno.
- Unique event IDs
- Each event carries an ID, in the body and in the Prontuno-Event-Id header, so a repeated delivery can be recognized.
- Automatic retries
- Failed deliveries are retried with increasing delays, so a brief outage does not lose events.
- Bounce details included
- Bounce events include the bounce type, the SMTP status code, and the receiving server’s diagnostic message.
{ "event_id": "evt_01kxx24h94e00v5rgamqhe607z", "webhook_id": "whk_01kxjf1tyje00bgxb0s9g4gfxn", "type": "email.bounced", "created_at": "2026-09-25T09:14:03.120Z", "data": { "email_id": "email_01kxwz4bfhe00rr3ww02remnap", "to_email": "ada@example.com", "subject": "Your receipt", "bounced_at": "2026-09-25T09:14:02.884Z", "reason": "Mailbox does not exist", "bounce": { "type": "permanent", "enhanced_status_code": "5.1.1" } }}import crypto from 'node:crypto'; function isValidSignature(rawBody, header, secret) { const parts = Object.fromEntries( header.split(',').map((part) => part.split('=')), ); const expected = crypto .createHmac('sha256', secret) .update(`${parts.t}.${rawBody}`) .digest('hex'); return ( typeof parts.v1 === 'string' && parts.v1.length === expected.length && crypto.timingSafeEqual(Buffer.from(parts.v1), Buffer.from(expected)) );}$payload = file_get_contents('php://input');$parts = []; foreach (explode(',', $_SERVER['HTTP_PRONTUNO_SIGNATURE'] ?? '') as $part) { [$key, $value] = array_pad(explode('=', $part, 2), 2, ''); $parts[$key] = $value;} $expected = hash_hmac('sha256', ($parts['t'] ?? '') . '.' . $payload, $secret); if (! hash_equals($expected, $parts['v1'] ?? '')) { http_response_code(401); exit;}Get started
Receive delivery events
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Step 1
Add a public HTTPS endpoint to your application.
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Step 2
Create a webhook in Prontuno, choose its events, and store the signing secret.
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Step 3
Verify each signature and skip event IDs you have already processed.
Compared
How other providers compare
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SES publishes delivery events to services such as Amazon SNS or EventBridge, which you connect and store yourself.
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SendGrid keeps 3 days of searchable activity on Essentials and 7 days on Pro. Prontuno keeps 30 days.
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Mailgun keeps 1 day of logs on Basic and 5 days on Foundation. Prontuno keeps 30 days.
More features
Explore the rest of Prontuno
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Send email with one HTTP request.
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Connect existing apps over SMTP.
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Set up SPF, DKIM, and DMARC.
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An IP reserved for your team.
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