SendGrid + Formspring: send form submissions in real time
Formspring + SendGrid for contact list management and templated email triggers. Submissions can both add a contact to a SendGrid list and trigger a templated email send via the SendGrid API.
Setup in 5 steps
- In SendGrid, create an incoming webhook URL (or equivalent) and copy it.
- In Formspring, open your form → Webhooks → Add webhook → paste the URL.
- Pick events to deliver (default: every successful submission).
- Save and send a test submission. The Formspring delivery log shows the response.
- Verify HMAC signatures in SendGrid (or your relay) using
X-Formspring-Signature: t=…,v1=….
Code examples
https://hooks.sendgrid.com/services/T0000/B0000/XXXXXXXXXWebhook payload shape
{
"submission_id": "fsm_01HRX...",
"form_id": "frm_abc123",
"created_at": "2026-05-07T10:24:00Z",
"data": {
"name": "Jane Doe",
"email": "jane@example.com",
"message": "…"
},
"meta": {
"ip": "203.0.113.10",
"user_agent": "Mozilla/5.0…",
"spam_score": 0.02
}
}Why connect SendGrid to Formspring
Real-time form notifications without polling. The moment a submission lands, SendGrid hears about it via signed webhook. Replace email-based form alerts with structured channel notifications, threaded conversations, or programmatic workflow triggers.
Reliability and retries
Formspring retries failed deliveries with exponential backoff (5 attempts over 24 hours). Every attempt is logged in the dashboard with response code, latency, and body. Use the Replay button to re-fire any past delivery.
Security: HMAC signing
Every webhook request to SendGrid (or your relay) carries an X-Formspring-Signature: t=<timestamp>,v1=<sha256-hmac> header. Verify in 3 lines (constant-time compare) to confirm the request came from Formspring and wasn't tampered with.
Custom payload shape
On Pro+ plans, you can transform the payload before delivery - pick fields, rename them, add static metadata, or filter by spam score. Useful when SendGrid's expected shape doesn't match Formspring's default.