Introduction
Inbox rendering lets you see how an email message displays across different email clients, platforms, and ISPs before sending a campaign. Running an inbox rendering check before each sendout helps ensure that both the message design and the sendout settings are correctly configured.
The check takes only a few minutes and provides concrete feedback to help optimize rendering, deliverability, and overall user experience. Inbox rendering is a standard feature in Mapp Engage and helps ensure message quality before they reach recipients.
Your system includes a defined number of inbox rendering tests. If you exceed this limit, additional charges apply. Contact your account manager for more information about available limits and pricing.
Common Use Cases
Inbox rendering is commonly used to:
Preview how an email message appears across multiple email clients and devices
Identify layout, formatting, or image display issues early
Compare message appearance with images enabled versus images suppressed
Check for potential spam-related issues and validate sender authentication
Review subject line length, list-unsubscribe headers, and links
Rendering Process and Results
Inbox rendering is performed by sending the email message to seed addresses across different platforms, email clients, and ISPs. For each environment, a screenshot of the message is captured and displayed as a thumbnail, so you can visually review how it renders in each client.
This process provides realistic insight into how recipients are likely to experience the message and helps identify rendering or configuration issues before the actual campaign sendout.
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Note:
Inbox rendering is an actual sendout to test addresses, not an artificial simulation.
Image Display Considerations
Inbox rendering lets you review messages with images displayed or suppressed. Many email clients block images by default, which means recipients may initially see only text and placeholders.
Reviewing message rendering without images helps you understand what information remains visible when graphics are not shown. While ALT text can improve accessibility, not all email clients display it consistently. Rendering checks without images highlight how image blocking can significantly impact the effectiveness of an email message in the inbox.