Mailgun vs Postmark for developers

Here’s the short developer-focused take:

Quick summary

• Postmark: best if you want excellent deliverability for transactional email, a very clean developer experience, and minimal setup.
• Mailgun: best if you want more flexibility, more features around email infrastructure, and potentially lower cost at scale, but with a bit more complexity.

Developer experience

Postmark

• Very polished docs and API
• Simple mental model
• Great for:
  • password resets
  • receipts
  • verification emails
  • app notifications
• Less “email platform sprawl”

Mailgun

• Powerful API
• More knobs and features
• Better if you need:
  • inbound email handling
  • parsing
  • routing
  • advanced domain/email workflows
• Docs are solid, but the product can feel more sprawling

Deliverability

• Postmark is widely regarded as stronger for transactional deliverability
• Mailgun can deliver well too, but you may need more tuning and monitoring depending on your setup

Features

Postmark strengths

• Transactional email focus
• Message streams
• Good analytics around delivery/open/click events
• Inbound support exists, but it’s not the main draw

Mailgun strengths

• Inbound routes and parsing
• Email validation
• Flexible routing
• More general-purpose email infrastructure

Pricing

• Mailgun can be attractive for higher volume or broader use cases
• Postmark may feel more expensive, but many developers consider it worth it for reliability and simplicity

Best choice by use case

Choose Postmark if:

• you primarily send transactional emails
• you care most about deliverability and simplicity
• you want the least amount of email ops work

Choose Mailgun if:

• you need inbound email processing
• you want more advanced email infrastructure features
• you have mixed transactional and workflow needs

My recommendation

If you’re building a product and mainly sending transactional emails, I’d usually pick Postmark.

If you want, I can also give you:

1. a feature-by-feature comparison table,
2. a pricing comparison, or
3. a recommendation based on your exact stack/use case.