Mailgun review covering the transactional email API, deliverability tools, 2026 pricing tiers, pros and cons, and top alternatives for developers.
Category
Email Marketing
Pricing
Usage-based subscription, from Free (100 emails/day); paid plans from $15/month
Verified
Not yet
Last updated
July 18, 2026
Founded
2010
Headquarters
Part of Sinch AB, Stockholm, Sweden (originally founded in San Francisco, California)
Free PlanWeb AppAPI
Overview
Mailgun is a transactional email API built for developers, letting applications send, receive, and track email programmatically rather than through a marketing campaign interface.
Founded in 2010 and now owned by Sinch after passing through Rackspace and an independent spinout as Pathwire, Mailgun remains one of the longest-running API-first email providers, known for pairing sending infrastructure with deliverability and validation tooling.
Key Features
Mailgun's product suite includes Send for core API/SMTP email delivery, Validate for real-time and bulk address verification, Optimize for deliverability monitoring, and Inspect for previewing how emails render across different clients.
Additional capabilities include inbound email parsing and routing, detailed sending logs and webhooks, dedicated IP addresses, SAML SSO on higher tiers, and DKIM/SPF/DMARC configuration support to protect sender reputation.
Pricing
Mailgun's free plan allows up to 100 emails per day with access to the core API and SMTP relay, one sending domain, and basic tracking and webhooks.
Paid plans scale by monthly email volume, starting around 15 dollars per month for 10,000 emails and rising through Foundation and Scale tiers that add features like template building, dedicated IP pools, and SSO, with custom Enterprise pricing for very high volumes.
Key Features
Transactional email API and SMTP relay — RESTful API and SMTP relay for sending programmatic email from applications.
Email validation — Real-time and bulk address verification to reduce bounces before sending.
Deliverability optimization — Monitoring and tooling to help maintain sender reputation and inbox placement.
Email rendering previews — Inspect emails across different clients and devices before sending, powered by Email on Acid.
Inbound routing and parsing — Receive and programmatically process incoming email through the API.
Webhooks and analytics — Track opens, clicks, bounces, and spam complaints via webhooks and dashboards.
Dedicated IP pools — Optional dedicated sending IPs available on higher-tier plans for reputation control.
SAML SSO — Single sign-on support for teams on the Scale and Enterprise tiers.
Pros & Cons
Pros
Mature, well-documented API with a long track record since 2010
Built-in email validation reduces bounce rates and protects sender reputation
Flexible product suite covering sending, validation, and rendering checks
Usage-based pricing scales predictably with sending volume
Backed by Sinch's broader communications infrastructure and reliability
Cons
Free tier is limited to 100 emails per day
Pricing and features have shifted since becoming part of a larger public company
Advanced features like SSO and dedicated IP pools require higher-cost plans
Primarily built for developers, with less appeal for non-technical marketers
Support quality on lower tiers is more limited than on Scale/Enterprise plans
Pricing
Free $0/month Monthly
Basic From $15/month Monthly
Foundation From $35/month Monthly
Scale From $90/month Monthly
Enterprise Custom Custom
Frequently Asked Questions
What is Mailgun used for
Mailgun is used by developers to send transactional email, such as password resets, receipts, and notifications, programmatically through an API or SMTP relay.
Is Mailgun free
Mailgun offers a free plan limited to 100 emails per day; paid plans start around 15 dollars per month for higher volumes.
Who owns Mailgun now
Mailgun is owned by Sinch, a Swedish communications platform company, which acquired it along with Mailjet through the 2021 Pathwire acquisition.
When was Mailgun founded
Mailgun was founded in 2010 by Ev Kontsevoy and Taylor Wakefield and went through Y Combinator in 2011.
Does Mailgun validate email addresses
Yes, Mailgun's Validate product offers real-time and bulk email address verification to help reduce bounces.
What are the main alternatives to Mailgun
Common alternatives include SendGrid, Amazon SES, Postmark, SparkPost, and Mailjet.