Mailgun vs Calendly
Email API for developers with deep deliverability tooling
vs. The scheduling category leader — dominant polished SaaS booking tool
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
Calendly
Free
$0. 1 user. 1 event type. Unlimited 1-on-1 meetings. Basic calendar integrations.
Free
Standard
$12/user/mo. Unlimited event types. Group events. Remove branding. 7 integrations.
$12/mo
Teams
$20/user/mo. Round-robin, collective, Salesforce/HubSpot, Zapier, routing, metrics.
$20/mo
Enterprise
Starts ~$15,000/year (5-10 users). SSO, SCIM, advanced routing, dedicated success manager, SLA.
$15000/mo
Free-tier quotas head-to-head
Comparing free on Mailgun vs free on Calendly.
| Metric | Mailgun | Calendly |
|---|---|---|
| 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_…
Calendly · 16 features
- Admin Management — Centralized team billing + controls.
- Analytics — Team conversion + activity.
- Availability — Schedules + recurring hours.
- Buffers — Before/after meetings.
- Daily / Weekly Limits — Cap bookings.
- Event Types — One-off, group, collective, round-robin.
- HubSpot Integration — Native sync.
- Inline + Popup Embed — Widget for websites.
- Marketing Routing — Form-based routing to teams/reps.
- Meeting Polls — Group availability poll (like When2Meet).
- Paid Bookings — Stripe integration.
- Round-Robin — Distribute across team.
- Salesforce Integration — Native, deep sync (Teams+).
- SSO — Enterprise only.
- Webhooks — Real-time events.
- Workflows — Automated reminders + follow-ups.
Developer interfaces
| Kind | Mailgun | Calendly |
|---|---|---|
| SDK | mailgun.js (Node), mailgun-php, mailgun-python, mailgun-ruby | — |
| REST | Mailgun REST API | Calendly REST API |
| OTHER | Inbound Routing, SMTP Relay, Webhooks | Calendly App, Calendly Embed Script, Calendly Webhooks, Chrome Extension, Zapier Integration |
Staxly is an independent catalog of developer platforms. Some links to Mailgun and Calendly may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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