SMTPfast vs Mailgun.

A leaner email API when you do not need Mailgun's broader routing and validation suite.

Mailgun is a long-running developer email platform with REST, SMTP, validation, and inbound routing. SMTPfast focuses on high-leverage sending workflows: Resend-compatible API, SMTP bridge, SES-backed domains, live logs, suppressions, and broadcasts.

SMTPfast

Straightforward plan limits for outbound email volume.

Mailgun is broader; SMTPfast is easier to reason about for outbound product email.

Mailgun

Usage and plan packaging across sending, validation, and add-ons.

Best for: Teams that need email validation and inbound routing alongside delivery.

What SMTPfast adds

The useful differences for teams evaluating Mailgun.

Broadcast campaigns and signup forms alongside transactional sends.
Real-time live tail for delivery debugging.
Warmup and account-safety controls aimed at new SaaS senders.
Resend-compatible API path for modern app migrations.

Short verdict

Choose Mailgun if validation and inbound routing are first-class requirements today. Choose SMTPfast if the core need is outbound API/SMTP sending with SES-backed deliverability, modern logs, suppressions, broadcasts, and a simpler SaaS dashboard.

Try SMTPfast free

Feature	SMTPfast	Mailgun
Pricing model	Simple volume plans	Usage plus packaged tiers
Public free tier	3,000 emails/month	100 emails/day
API & Sending
REST API
Resend-compatible payloads
SMTP relay
Batch sending	100/request
Idempotency keys
Inline images (cid) and automatic plain text
Customer webhooks
Share links for sent emails		Not published
Marketing & Audience
Broadcast campaigns
Signup forms
Workflow automation	Planned
Dynamic segments	Planned
Hosted templates	Planned
Deliverability & Safety
DKIM/SPF/DMARC guidance
Custom MAIL FROM
Suppression management
Live event tail
Warmup and abuse controls
Platform Model
Inbound email	Paid plans	Routes
MCP server for AI agents
Terraform provider	Official	Community
API key scopes	Per key	Domain keys
Open source	Evaluating
Self-hostable	Evaluating
Team members and roles	Paid plans
No per-seat pricing

Choose Mailgun if

You need email validation as a core paid feature.
You need rule-based inbound routing, not just receiving.
Your team already uses Mailgun's APIs and SDKs deeply.

Choose SMTPfast if

You want an outbound-first platform with a cleaner SaaS workflow.
You need SMTP bridge plus modern REST sends and live debugging.
You want broadcasts and signup forms without adopting a full marketing suite.

Migration checklist

1Map Mailgun domains, routes, templates, tags, and webhooks.
2Create an SMTPfast account and generate an API key with email:send scope.
3Add and verify your sending domain with DKIM, SPF, DMARC, and MAIL FROM records.
4Send a low-volume test message and confirm events appear in the SMTPfast logs.
5Move production traffic gradually while watching bounces, complaints, and suppressions.
6If you depend on Mailgun Routes, keep them there. SMTPfast receives, parses and webhooks inbound mail, but does not match it against forwarding rules.

Frequently asked questions.

Is SMTPfast better than Mailgun?

Mailgun is stronger for validation and inbound routing. SMTPfast is stronger when you want simpler outbound sending, SES-backed domain controls, live logs, suppressions, broadcasts, and signup forms.

When should I still choose Mailgun?

Choose Mailgun when its core strength matches your team: Teams that need email validation and inbound routing alongside delivery. SMTPfast is a better fit when you want a developer-first SES-backed API with queues, webhooks, tracking, suppressions, and a focused dashboard already handled.

How hard is it to migrate from Mailgun to SMTPfast?

Most migrations start with domain verification, a test API key, and one low-risk transactional email path. Resend-compatible payloads are especially quick to move; older providers may require mapping template, webhook, and suppression behavior.