Mailgun is a developer-focused transactional email sending API used by more than 150,000 businesses. Known for its powerful analytics, flexible routing rules, and excellent documentation, it is the preferred email infrastructure choice for engineering teams that need precise control over deliverability, bounce handling, and email event tracking.
Product Overview
Mailgun's key differentiator for technical teams is its Email Logs and webhooks system: every send, delivery, open, click, bounce, and spam complaint is available as a real-time event that can trigger downstream automation. Inbound routing allows teams to receive, parse, and forward emails programmatically — useful for processing reply emails in sales automation workflows. Its Mailgun Optimize suite provides inbox placement testing, email preview across clients, and spam filter testing before sending campaigns.
Key Features
- Sending API: RESTful email sending API with SMTP relay, batch sending, and per-message variable substitution for personalisation.
- Event Webhooks: Real-time webhooks for every email event — delivered, bounced, opened, clicked, complained — for automation triggers.
- Inbound Email Routing: Receive, parse, and forward inbound email programmatically — useful for reply handling in sales sequences.
- Mailgun Optimize: Inbox placement testing, spam filter analysis, and email client preview before sending to your list.
- Email Validation API: Real-time and bulk email address validation with syntax, DNS, and mailbox existence checks.
Best For
Engineering teams building applications that need programmatic email sending with precise event tracking, inbound email processing, and detailed deliverability analytics.
Pricing
Free plan (100 emails/day for 3 months). Foundation from $35/month (50K emails); Scale from $90/month; Custom for high volume.
Key Integrations
Zapier, WordPress, Shopify, HubSpot, Salesforce, AWS Lambda, REST API (any platform)
Pros
- Best developer documentation and webhook system in the category
- Inbound email routing enables reply-handling automation
- Mailgun Optimize deliverability testing is valuable pre-send
- Flexible routing rules for complex email workflows
Cons
- No visual email builder — code or API only
- Less suited for non-technical marketing teams
- Pricing less competitive than SendGrid at very high volume
