Void Relay is a developer-friendly email API that lets you send emails through your own SMTP server while providing a modern REST API, real-time webhooks, and email tracking — eliminating vendor lock-in.
What is Void Relay?
Void Relay is a REST API that accepts email requests and delivers them via your own SMTP infrastructure (such as Gmail, SendGrid, Mailgun, or AWS SES). It runs on a global edge network for low-latency processing and provides real-time webhooks for delivery events. The service is built and maintained by the Voidvalue team. You can get started free at relay.voidvalue.com.
Key Features
- No vendor lock-in — Use any SMTP provider you choose; you are never tied to a single email service.
- Developer-friendly REST API — Send emails with a single HTTP request; compatible with any programming language.
- Real-time webhooks — Receive notifications for sent, delivered, failed, opened, and clicked events.
- Powerful analytics — Monitor delivery performance with detailed logs and real-time dashboards.
- Global edge network — Requests are processed at edge locations closest to your SMTP server for fast delivery.
- TypeScript/JavaScript SDK — Official npm package with full type safety; Python, Go, Ruby, and PHP SDKs coming soon. See documentation for code examples.
- Unlimited SMTP servers — Configure multiple SMTP servers on all plans.
- Free tier with generous limits — Up to 2,500 emails/day per API key (5 API keys = 12,500/day total); beta users receive 5,000 emails/day per API key forever.
Who should use Void Relay?
- Developers building email features who want the convenience of a modern API like Resend but need to control their email infrastructure.
- Startups and small teams that want to avoid vendor lock-in and keep their email sending flexible.
- Tech companies already using SMTP who want to add webhooks, analytics, and a simple API without switching providers.
What can you do with Void Relay?
- Send transactional emails via Gmail, SendGrid, or any SMTP server — Configure your own SMTP credentials and use the API to send emails.
- Track email delivery events — Set up webhooks to receive real-time updates on opens, clicks, bounces, and delivery status.
- Integrate with any language or framework — Use the REST API directly or the TypeScript/JavaScript SDK; cURL, Python, Go, Ruby, PHP, and more are supported.
Pricing
Void Relay offers a Free plan with 2,500 emails/day per API key (up to 5 API keys) and a Pro plan coming soon at $2/month with 20 API keys, priority support, advanced analytics, and team collaboration. Beta users receive 5,000 emails/day per API key forever. Sign up for the beta here.









