Mailosaur for...

Engineering

Automate and test email and SMS workflows

Quality Assurance

Empower your team and improve email quality

Product Management

Demo and improve your product using email and SMS

Marketing

Deliver high-quality, targeted email campaigns

Solutions

Email Testing

Create end-to-end tests that depend on email

SMS Testing

Automate and use SMS messages during testing

Email Previews

View your email in Gmail, Outlook and mobile devices

Test automation

See how easy it is to automate all the tests you thought you couldn't

Features

Rules

Create automated rules that simulate every type of scenario including email bounces and out-of-office replies

Custom Domains

Unlimited recognisable email addresses for your brand

Enterprise SSO

Centralized security for your organization

Forwarding Rules

Set up rules that automatically forward your emails to certain inboxes

Links and Codes

Peace of mind that you are sending exactly what you mean to, everytime

Message Analysis

Ensuring the quality of your content is never compromised

Sending, Replying and Forwarding Emails

Seamless email and SMS interactions, every time

Virtual SMTP Servers

Use Mailosaur as a dummy SMTP server to catch every email your product sends

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Blog

Explore the Mailosaur blog for expert insights on email & SMS testing, automation, and quality assurance

"Most common rendering issues in 2026" with two screenshots of the same email on the right - one in dark mode with images and personalisation broken, and one in light mode with everything rendering as expected.

Best practices

The most common email rendering issues in 2026 (and how to fix them)

Designing HTML emails that render consistently across inboxes remains one of the biggest technical challenges in digital communication.

"The structure of an email" with an annotated email to the right showing labels such as "email address" and "personalised name"

Best practices

How modern emails are structured (and how to test them)

Understand the anatomy of a modern email, from headers to HTML, and how to reliably test them with a dedicated email testing tool like Mailosaur.

Best practices

The ultimate guide to SMS testing

From manual checks to fully automated workflows, here’s how to test SMS with confidence.

Mailosaur vs Competitors

Choosing the best email preview tool for you in 2026

Rising prices or limited functionality forcing you to look for a new tool? Take a look at our side by side comparison so you can make an informed decision.

News

How Selenium 4.40 improves end-to-end email verification testing

What's changed in Selenium 4.40 and how will it benefit you when testing email verification flows?

"Functional vs non-functional testing" with a simplified version of the Mailosaur UI on the right

Best practices

Functional vs non-functional: Which should I use for email testing?

Functional testing makes sure the information input into the system outputs the correct results, and non-functional testing covers parameters that functional testing doesn’t, like security, reliability, and performance.

Best practices

How to write and test alt text for emails in 2026

Boost email accessibility, rendering consistency, and engagement by implementing better alt text strategies.

Best practices

Top tips for email testing in CI/CD pipelines

Automate email verification, catch failures early, and protect user trust without manual guesswork.

Abstract green background with test running dialog and pass and fail results

Best practices

Flaky email tests; the problem, causes and solutions

Don't let flaky tests impact your release times, drive-up maintenance costs, or impact your team morale.

Abstract green background with email and mobile illustration with security icon

Best practices

The biggest hidden complication in email and SMS testing

Learn how to ensure privacy, data protection, and secure workflows with compliant test environments for QA and automation.

Dark and light mode emails with Mailosaur and Mailtrap logos and running test dialogs

Mailosaur vs Competitors

The ultimate email testing tool: comparing Mailosaur and Mailtrap

Wondering which email testing tool is best for your team? Check out a real side by side comparison and make an informed choice.

Playwright

Automate email verification testing in Playwright (links + OTPs)

Test email verification flows, including magic links and OTPs quickly and easily with Playwright

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