Industry-leading email testing
Error-Free emails are a preview test away
You spend hours, days, weeks crafting the perfect email only to hit send and realize it rendered wrong on thousands of recipient devices. With so many new devices and clients coming out every year, it can be nearly impossible to ensure your email looks perfect on each one without help from the right preview tool.
Display your message as intended —on every device, in every inbox. Deliver error-free messages in less time with testing on 100+ devices and clients (including dark mode)
Dynamic email testing
Stand out in a crowded inbox
You made it to the inbox, but your email still needs to be opened. With tons of other emails also competing for the same attention, it can be hard to stand out visually.
Go beyond previews by testing the inbox-view of your sender name, subject line, and preheader text across phone, desktop, and web. Play with word count, alter copy, adjust spacing and see what works best for your email.
Comprehensive results
Dark mode optimization
Test and preview in dark mode so your email matches branding guidelines, images with transparent backgrounds are visible, your text is the right color, and more.
With over 82% of people using some form of dark mode on their devices, be set up for success no matter how your recipients consume email.
Flexible previews
Email previews for every sender
Integrate email previews into your existing API set for a complete email management stack. Create a better email workflow with content validation checkpoints you can trust on every email campaign.
Whether you have a hundred or a million emails to preview, you’re covered.
Email Preview FAQ
What is email preview?
Email preview is a tool that allows you to see how your email’s design, formatting, and content display correctly across various platforms, such as Gmail, Outlook, and different mobile devices before you hit send. Email previews allow for easy identification and remedy of formatting issues, broken links, or misaligned content before emails reach your recipients. With different email clients rendering content differently, previewing emails ensures that your message looks great for all users, regardless of their platform.
What does an email preview cover?
An email preview covers how your email will appear across a wide variety of devices and email clients. This includes checking layout, font rendering, image display, and link functionality. Essentially, it helps you visualize your email as recipients would see it.
Are the generated previews just HTML rendering or actual device/client simulations?
The email previews generated by Mailgun are not just HTML renderings—they simulate how the email will appear in real device/client environments. This includes capturing the rendering behavior of specific email clients and devices, so you see exactly how your email will look across different platforms like mobile phones, desktops, and various email clients.
What devices and clients are supported by the HTML Email Preview API?
Mailgun’s HTML Email Preview API supports a wide range of devices and clients, including popular platforms such as Gmail, Outlook, Apple Mail, Yahoo, and many mobile devices like iPhone, Android, and iPad. Emails render correctly across a broad spectrum of environments used by your audience.
How can I integrate email previewing into my development workflow?
You can easily integrate Mailgun’s email previewing tool into your development workflow by using our Email Preview API. This allows you to automate the process of testing email designs across different clients and devices. Simply upload your HTML to Mailgun, select the devices and clients you want to preview, and then render, and it will generate previews for various clients and devices, saving you time and ensuring consistency in your email campaigns.
What specific error types can be caught before sending emails?
Mailgun’s email preview tool can catch a range of issues before sending emails, including:
Rendering issues: Ensures your email looks correct across various email clients.
Broken links: Detects any invalid URLs that might lead to broken links.
Missing images: Identifies if any images in the email fail to load properly.
Incorrect personalization tags: Highlights any issues with dynamic content or personalization tags that might fail during the send.
Layout problems: Detects misalignments or issues with responsive design across devices.
By catching these errors early, you ensure a smoother, more professional email experience for your recipients.