Mailgun vs GrowthBook
Email API for developers with deep deliverability tooling
vs. Open-source feature flags + experimentation — Warehouse Native
Pricing tiers
Mailgun
Free
100 emails/day. 1 custom domain, 1-day log retention, 1 inbound route. No credit card.
Free
Basic
$15/month. 10,000 emails/month, no daily limit, 5 inbound routes.
$15/mo
Foundation
$35/month (1st month free). 50,000 emails/month, 1,000 custom domains, 5-day retention.
$35/mo
Scale
$90/month. 100,000 emails/month, SAML SSO, 5,000 email validations, dedicated IP pools, 30-day retention.
$90/mo
Enterprise
Custom. Deliverability services, managed onboarding.
Custom
GrowthBook
Open Source (Self-Host)
MIT-licensed. Unlimited everything. Community support.
$0 base (usage-based)
Cloud — Starter (Free)
Up to 3 users. Unlimited flags + experiments. Warehouse Native included.
Free
Cloud — Pro
$40/user/month. Up to 50 users. Advanced stats, visual A/B editor, CUPED, sequential testing, bandits.
$40/mo
Cloud — Enterprise
Custom. Unlimited users, SSO/SAML, approval flows, data pipelines, exportable audit logs.
Custom
Self-Host Enterprise
Open Source + Enterprise license. Visual A/B editor, advanced metrics, SSO/SAML, approvals, training.
Custom
Free-tier quotas head-to-head
Comparing free on Mailgun vs oss on GrowthBook.
| Metric | Mailgun | GrowthBook |
|---|---|---|
| No overlapping quota metrics for these tiers. | ||
Features
Mailgun · 14 features
- Batch Sending — Send up to 1,000 recipients per API call via recipient variables.
- Dedicated IPs — IP pools with auto warmup. Scale+ tier.
- Deliverability Suite — Inbox placement testing, DMARC reporting, seed lists.
- Email Logs — Searchable log of all send attempts + events.
- Email Templates — Template builder + variables + versioning.
- Email Validation — Real-time email verification (syntax, MX, role accounts, disposable).
- EU Region — Data stored in EU for GDPR-sensitive customers.
- Inbound Routing — Route incoming emails to URLs/SMTP. Attachment forwarding.
- Mailing Lists — Unlimited mailing lists with bulk subscribe/unsubscribe.
- Open/Click Tracking — HTML + text tracking with configurable tracking domain.
- SAML SSO — Scale+ tier.
- Send API — REST/SMTP send with MIME + tracking.
- Tags — Tag messages to slice stats.
- Webhook Events — delivered, opened, clicked, unsubscribed, complained, permanent_fail, temporary_…
GrowthBook · 15 features
- Approval Flows — Require reviewer approval on flag changes. Enterprise.
- Audit Logs — Full change history. Exportable on Enterprise.
- Dimensions & Slicing — Break down experiment results by user dimensions.
- Edge SDK Support — Cloudflare Workers, Lambda@Edge, Fastly, Akamai EdgeWorkers, Netlify Edge.
- Experiments — A/B/n with CUPED variance reduction + sequential testing.
- Feature Flags — Boolean + string + number + JSON flags with targeting.
- Feature Reviews (PR-style) — Draft → review → approve flag changes.
- Guardrail Metrics — Auto-monitor key metrics during experiments.
- Metric Catalog — Define + reuse metrics across experiments.
- Multi-Armed Bandits — Adaptive traffic allocation. Pro+.
- Safe Rollouts — Guarded gradual rollouts with automatic rollback.
- SSO / SAML — Enterprise SSO for cloud + self-host EE.
- Sticky Bucketing — User stays in variant even after eligibility changes.
- Visual A/B Test Editor — No-code DOM editor for web experiments. Pro+.
- Warehouse Native — Connect your warehouse + run experiments against your events data.
Developer interfaces
| Kind | Mailgun | GrowthBook |
|---|---|---|
| SDK | mailgun.js (Node), mailgun-php, mailgun-python, mailgun-ruby | Edge SDKs (CF Workers / Lambda@Edge / Fastly / Akamai), growthbook-android, growthbook-flutter, growthbook-go, growthbook-java, growthbook-node, growthbook-php, growthbook-python, growthbook-ruby, growthbook-swift, sdk-javascript, sdk-react |
| REST | Mailgun REST API | GrowthBook REST API |
| OTHER | Inbound Routing, SMTP Relay, Webhooks | Webhooks |
Staxly is an independent catalog of developer platforms. Outbound links to Mailgun and GrowthBook are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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