Display issues: why emails appear differently across platforms

Even with careful design, newsletters can look different depending on which email client a subscriber uses. Here's why — and what you can do about it.

Why emails look different across platforms

Email clients (Gmail, Outlook, Apple Mail, mobile apps) each interpret HTML and CSS differently. There's no universal rendering engine for email the way there is for web browsers, so the same email can look polished in one client and slightly off in another.

Outlook is the most common source of display issues — it renders email HTML using Microsoft Word's print-centric engine, which doesn't support many modern CSS properties.

What you can do

• Always preview before sending — use the Preview button in the dashboard to check how your newsletter looks on desktop and mobile before it goes out. See Sending test emails and previewing.
• Send test emails to multiple addresses — test in Gmail, Outlook, and Apple Mail if possible to catch rendering differences early.
• Test in dark mode — many subscribers use dark mode, which can affect how colors and images appear.
• Authenticate your domain — this improves trust with email clients and can reduce the likelihood of display issues caused by security filters. See How to authenticate your domain.

Outlook-specific issues

If your newsletter looks correct everywhere except Outlook, this is a known limitation of Outlook's rendering engine. Our templates are designed to handle the most common Outlook quirks, but some differences may remain. Contact support@rasa.io if you're seeing a significant rendering issue in Outlook — our team can help investigate and fix template-level problems.