Mailgun

Mailgun is a transactional email API and SMTP relay for developers, with paid add-ons for deliverability monitoring, pre-send QA and email validation.

Mailgun is a transactional email API and SMTP relay for the mail that applications send automatically: receipts, password resets, shipping updates and account alerts. Sinch AB has owned it since its Pathwire acquisition closed on 7 December 2021, and Mailgun's site now carries the Sinch Email branding while the product keeps its own name. One login covers four parts on one pricing page. Send is the sending itself: a REST sending API, an SMTP relay, inbound email parsing, delivery event webhooks, bulk and batch sending, suppression list management, server-side email templates, a sandbox test mode, scheduled delivery, bounce classification, official client libraries and EU and US data residency from a single account, with dedicated IP pools and automated warm-up, Send Time Optimization, SAML single sign-on and live support on the top self-serve tier. Optimize is the deliverability add-on, with inbox placement testing, DMARC report analytics, blocklist monitoring, IP and domain reputation tracking and Google Postmaster Tools and Microsoft SNDS integration. Validate checks addresses before a send, in bulk or in real time, sold as credits. Inspect previews a message across more than 100 devices and inbox clients with accessibility, HTML, link and spam content QA. Subaccounts with separate sending domains, IPs and API keys per stream sit behind an Enterprise contract. Mailgun suits developers integrating transactional email by API or SMTP, teams that want deliverability monitoring and pre-send QA under the same login rather than a separate vendor, and senders that need to send from a US or an EU region on one account. Send is sold on a permanently free plan and the Basic, Foundation and Scale tiers, sized by monthly email volume and billed month to month, with Optimize and Inspect as monthly add-ons, Validate as credits and the largest senders on Enterprise contracts. The plan cards list every tier. In daily use Mailgun sends the receipts, password resets and notifications from an application, parses inbound replies and routes them into a system, tests inbox placement and spam-folder rates before a send, validates a list ahead of a campaign and checks how an email renders across clients. It sits beside the application that calls it and, for campaigns with a drag-and-drop builder, beside Mailjet, Sinch's marketing email product, rather than replacing either.