Webhooks API for Developers
Real-time notifications for post delivery, engagement milestones, and account events. Never poll for status again.
No credit card required · Full API access
Features
Everything you need
Delivery Confirmations
Receive an instant webhook when a post is successfully published on each platform. Includes the live URL, platform-specific post ID, and final rendered content.
Engagement Alerts
Get notified when posts hit engagement milestones — 100 likes, 1K impressions, first comment, or custom thresholds you define. React to viral content in real time.
Failure Notifications
Know immediately when a post fails to publish, with detailed error codes, failure reasons, and whether a retry is scheduled. Build alerts or fallback flows without delay.
Account Events
Monitor account-level changes — token expirations, permission changes, rate limit warnings, and disconnections. Stay ahead of issues before they affect your users.
Configurable Retry Logic
Failed webhook deliveries are retried up to 5 times over 24 hours with exponential backoff. View delivery attempts, response codes, and timing in the webhook logs.
Webhook Signing & Verification
Every webhook payload is signed with HMAC-SHA256 using your endpoint's secret key. Verify signatures server-side to ensure payloads are authentic and untampered.
Event Filtering
Subscribe to exactly the events you care about. Filter by event type, platform, workspace, or post tags. Reduce noise and processing overhead with precise subscriptions.
Batch Events
For high-volume use cases, enable batch mode to receive multiple events in a single webhook delivery. Reduce HTTP overhead and simplify processing for busy integrations.
How It Works
Up and running in minutes
Get Your API Key
Sign up and generate your credentials in seconds.
Connect Social Accounts
Link platforms via OAuth with our guided setup flow.
Start Building
Use the API to publish, manage, and track content across all platforms.
Why Developers Choose RelayAPI
One Webhook, Every Platform
Building a reliable polling system across 17 platforms is fragile and expensive. RelayAPI pushes events to you the moment they happen, replacing thousands of polling requests with a single webhook endpoint.
Enterprise-Grade Reliability
Webhooks are delivered with 99.9% reliability backed by automatic retries, dead-letter queues, and delivery logging. Every event is stored for 30 days so you can replay missed deliveries at any time.
Developer-First Experience
Test webhooks locally with our CLI tunnel, inspect payloads in the dashboard, replay past events with one click, and use our SDKs for signature verification. Debugging webhooks has never been easier.
Quick Start
Start building in minutes
curl -X POST https:"color:#6a9955">//api.relayapi.dev/v1/webhooks \
-H "Authorization: Bearer rlay_live_xxxxxxxx" \
-H "Content-Type: application/json" \
-d '{
"url": "https:">//yourapp.com/webhooks/relayapi",
"events": [
"post.published",
"post.failed",
"post.engagement_milestone",
"account.disconnected"
],
"secret": "whsec_your_signing_secret_here"
}'
"color:#6a9955"># Response:
"color:#6a9955"># {
"color:#6a9955"># "id": "wh_m3n4o5p6q7",
"color:#6a9955"># "url": "https://yourapp.com/webhooks/relayapi",
"color:#6a9955"># "events": ["post.published", "post.failed", "post.engagement_milestone", "account.disconnected"],
"color:#6a9955"># "status": "active",
"color:#6a9955"># "created_at": "2026-03-20T10:30:00Z"
"color:#6a9955"># }Frequently Asked Questions
Ready to Start Building?
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