Build Custom Integrations with WarmySender API
Connect your Webhooks & API mailbox to WarmySender and build the sender reputation that lands cold email in the inbox — with warmup, campaigns, and multichannel outreach on autopilot.
- RESTful API design
- Webhook event notifications
- API key authentication
- Comprehensive documentation
- Rate limiting with fair usage
- Sandbox environment for testing
Key takeaways
- Is there API documentation? Yes. Full API documentation is available at docs.
- What's the rate limit? 1,000 requests per hour per API key.
- Can I test without affecting production? Yes. We provide a sandbox environment for development and testing.
API Overview
WarmySender's REST API enables custom integrations for teams with specific requirements. Whether you're building internal tools, connecting to proprietary systems, or creating automated workflows, our API provides the access you need.
Authentication
All API requests authenticate using API keys:
Authorization: Bearer your_api_key_hereGenerate keys from Settings → API in your WarmySender dashboard. Keys can be revoked at any time.
Key Endpoints
Mailboxes
- GET /api/v1/mailboxes - List all mailboxes
- GET /api/v1/mailboxes/:id - Get mailbox details
- PATCH /api/v1/mailboxes/:id - Update mailbox settings
- DELETE /api/v1/mailboxes/:id - Disconnect mailbox
Warmup
- GET /api/v1/mailboxes/:id/warmup - Get warmup status
- POST /api/v1/mailboxes/:id/warmup/pause - Pause warmup
- POST /api/v1/mailboxes/:id/warmup/resume - Resume warmup
- PATCH /api/v1/mailboxes/:id/warmup - Update warmup settings
Analytics
- GET /api/v1/mailboxes/:id/stats - Get warmup statistics
- GET /api/v1/mailboxes/:id/health - Get health score
Webhooks
Receive real-time notifications when events occur:
- mailbox.connected - New mailbox connected
- mailbox.disconnected - Mailbox removed
- warmup.health_changed - Health status changed
- warmup.milestone - Warmup milestone reached
Configure webhook endpoints in Settings → Webhooks. All webhooks include a signature header for verification.
Rate Limits
API requests are limited to ensure fair usage:
- 1,000 requests per hour per API key
- Rate limit headers included in responses
- 429 status returned when exceeded
How to connect Webhooks & API
- Generate API Key
Create an API key from your WarmySender settings - Read Documentation
Review API docs for endpoints and authentication - Build Integration
Develop your custom integration using our API - Configure Webhooks
Set up webhook endpoints to receive events
What you get
- Automated warmup emails sent around the clock
- Real engagement from genuine, verified mailboxes
- Spam-folder detection and automatic rescue
- Detailed deliverability and inbox-placement analytics
- Manage multiple mailboxes from one dashboard
- Fully hands-off — no manual sending required
Frequently asked questions
Is there API documentation?
Yes. Full API documentation is available at docs.warmysender.com with endpoints, authentication, and examples.
What's the rate limit?
1,000 requests per hour per API key. This is sufficient for most integrations. Contact us if you need higher limits.
Can I test without affecting production?
Yes. We provide a sandbox environment for development and testing. API keys can be scoped to sandbox only.
How are webhooks secured?
All webhooks include an HMAC signature in the X-WarmySender-Signature header. Verify this signature to ensure requests are authentic.