Open-source alternative
for Mailgun
Mailgun is excellent for transactional emails. Plunk adds marketing campaigns, workflow automation, and is open-source.
The Pricing Model That Makes Sense
Pay for what you use, not fixed subscriptions
Pay per email sent
Pay-as-you-go pricing. Only pay for emails you actually send.
Tiered monthly plans
Monthly subscription with tiered email volume limits.
Feature-by-Feature
What Plunk Adds
Beyond transactional emails
Marketing Campaigns
Send one-time broadcasts to all contacts or specific segments. Schedule sends, track performance. Mailgun doesn't offer this.
Workflow Automation
Build multi-step email sequences with triggers, delays, and conditions. Perfect for onboarding, drip campaigns, cart abandonment.
Dynamic Segmentation
Create audience segments that update automatically based on contact data and behavior. Target campaigns precisely.
Open Source
AGPL-3.0 licensed. Inspect the code, contribute features, no vendor lock-in. Mailgun is proprietary.
Self-Hostable
Run on your infrastructure with Docker. Full data control, compliance-ready. Pay only AWS SES fees when self-hosting.
All-in-One Platform
One platform for transactional, marketing, and automation. No need for multiple tools or integrations.
Frequently asked questions
When should I choose Mailgun over Plunk?
Choose Mailgun if you need advanced email validation features or have very high volume transactional email needs (millions per day) and want a proven infrastructure provider. Mailgun has been around longer and has extensive deliverability tools. Choose Plunk if you need marketing campaigns, workflow automation, or want the flexibility to self-host (though Plunk also offers fully-managed hosting).
What is the pricing difference between Plunk and Mailgun?
Plunk uses a simple pay-as-you-go pricing model where you pay only for emails sent. Mailgun uses tiered monthly plans based on email volume, which can be cost-effective at very high volumes but less flexible for variable sending patterns. With Plunk, you get marketing campaigns and workflow automation included at no additional cost - with Mailgun, you'd need separate tools for marketing.
Is migration from Mailgun to Plunk complex?
Migration requires updating your API integration since Plunk and Mailgun use different API structures. You'll need to update your code to use Plunk's endpoints and parameter format. Both platforms support similar core features (templates, webhooks, custom domains), so the concepts translate directly. Plan for a few hours of development work to migrate your integration. Your email templates can be adapted with minimal changes.
What does Plunk add beyond transactional emails?
Plunk adds marketing campaigns (one-time broadcasts to all contacts or specific segments), workflow automation (multi-step email sequences with triggers, delays, and conditions), and dynamic audience segmentation (auto-updating groups based on contact data and behavior). These features mean you can handle both transactional and marketing emails in one platform. Plunk is also open-source (AGPL-3.0) and self-hostable, giving you full control over your email infrastructure.
Try Plunk free
1,000 emails/month free. No credit card required. Add marketing and automation when you need it.