17.9
MailSlurp provides tools to build, test, and automate email and SMS workflows.
Free planAndroidiOSWeb
Best Email Testing Software in 2026
MailSlurp leads this chart of 28 (7.9/10, free plan). Mailinator is next (7.8/10, free plan), and Emailens is the next highest-placed with a free plan (7.7/10). Before sending campaigns or other messages, you may want to check how they render and function across different inboxes. Compared on email clients, device coverage, inbox testing, spam checks, and link checks, these tools cover several parts of an email review. Accessibility checks and API access are additional criteria to weigh, depending on what you need to inspect and integrate. A free plan and paid-from pricing…
27.8
Mailinator provides temporary inboxes and email and SMS workflow testing for developers, QA teams, and businesses.
Free planAndroidWebAPI
37.7
Emailens previews how HTML email content renders across 21 email clients and checks compatibility across 298 CSS and HTML features.
Free planOpen sourceWebAPIExtension
- 4
GlockApps
GlockApps provides tools for testing email deliverability and monitoring technical issues that can affect message placement.
Free planWebAPI7.4From $59 a month - 5
Unspam.email
Unspam.email is an email deliverability platform for checking spam signals, sender authentication and campaign inbox placement.
Free planWebAPI7.4From $5 a month - 6
testmail.app
testmail.app receives and parses test emails, checks them for spam, and indexes them for API retrieval in automated end-to-end testing.
Free planWebAPI7.3From $9 a month - 7
Litmus
Litmus is an email workflow platform for teams building, testing, monitoring, and analyzing campaigns.
WebAPIExtension7.2From $79 a month - 8
SMTP Labs
SMTP Labs is an email testing service for receiving test messages and inspecting them in a web interface, through IMAP or POP3, or with its API.
Free planWebAPI7.2From $7 a month - 9
Mailpit
Mailpit is a free, open-source utility for developers who need to test email content and SMTP delivery without sending messages to real email addresses.
Free planWebAPILinuxmacOS6.9Free plan - 10
Postdrop
Free planWeb6.8From $29 a month - 11
Mailtrap Email Sandbox
Mailtrap Email Sandbox captures email traffic from development and staging systems so teams can examine messages before they reach real recipients.
Free planWebAPI6.7From $17 a month - 12
EmailQA
EmailQA helps teams review HTML email layouts by rendering previews and collecting comments pinned to specific locations.
Free planWebAPI6.6From $20 a month - 13
RenderOps
RenderOps is a browser-based email development suite with 36 tools for email engineers.
Free planWebAPI6.6From $10 a month - 14
Email Accessibility
Email Accessibility is a web service for checking email against WCAG 2.2.
Free planWeb6.5From $10 a month - 156.4From $15 a month
- 166.3Free plan
- 17
Mailosaur
Mailosaur captures email and SMS messages so teams can test communication workflows through a web dashboard and testing API.
WebAPI6.2From $20 a month - 18
Inbox Monster
Inbox Monster is a web platform for email creative review, inbox intelligence, and deliverability work.
Web6.0From $3,750 a year - 19
MailTester
MailTester checks why emails may land in spam and gives each message a deliverability score out of 10.
Free planWebAPISelf-hosted6.0Free plan - 206.0From $49 a month
- 21
Ethereal Email
Ethereal Email is a free email-catching service for testing outbound messages.
Free planWebAPI5.9Free plan - 22
MailCatcher
MailCatcher is a free, open-source tool for inspecting email that an application sends during development.
WebAPILinuxmacOS5.9 - 23
MailDev
MailDev is a free, local SMTP server and web inbox for developers checking email generated by applications during development.
Free planWebAPISelf-hosted5.9Free plan - 24
Mailgun
Mailgun is a web-based email service for sending and routing messages through RESTful email APIs and an SMTP relay.
Free planWeb5.8Free plan - 25
smtp4dev
smtp4dev is a free fake SMTP server for development and testing, letting teams inspect test email without sending it to real customers.
WebAPILinuxmacOS5.8