Campaign Operations
Part of Email testing before a send
Testing a template across email clients
Choose relevant email clients and check reading order, controls and dark-mode legibility before sending.
Test the final campaign in a small set of email clients relevant to its readers. Compare what people can read and do, not identical pixels. A template that looks sound in an editor may display differently in webmail, a desktop app or a phone inbox.
Testing Best Practices Summary
- Use audience data when possible
- Tailor testing to actual client usage patterns across Australia
- Test dark mode where relevant
- Ensure contrast meets accessibility standards for ATO and government-related emails
- Focus on usability over pixel-perfect match
- Content clarity and interaction success matter more than identical visuals
- Validate links and buttons in every environment
- Confirm actions work as expected—especially for online enrolment and payment flows
Choose the clients
Choose the sample from audience client data where possible. Include desktop and mobile views, and add a dark-mode view when colours or logos may lose contrast. If client data is unavailable, document the sample and its limits instead of calling it representative.
A practical named sample could include Gmail in Chrome, Outlook Office 365 on Windows 10, Apple Mail 16 on macOS 13, Gmail App on iPhone 15 (iOS 17), and Microsoft Outlook on Android 11. Treat these as sample options, not a substitute for audience data.
For dark mode, Litmus lists iPhone 15 Dark (iOS 17), Gmail App Dark (Android 11), and Outlook.com Dark in Chrome. These are named environments to consider when selecting relevant views.
Named preview options include Mailchimp Inbox Preview and Litmus. Litmus lists previews for 100+ popular email clients, including Dark Mode, in real time; use views relevant to the audience. Mailchimp recommends previewing and testing your email before sending.
Teams can also inspect test messages in inboxes they control. Screenshots show visual output, while received messages let reviewers try controls. Use the same client, device and settings when comparing a fix with an earlier test.
Email Client Testing Sample for Australian Audiences
- Gmail (Chrome, Desktop)Webmail – widely used in Australia; check responsive layout and link usability
- Outlook Office 365 (Windows 10)Common in Australian business environments; test table-based layouts and image rendering
- Apple Mail 16 (macOS 13)Popular among Australian creatives and professionals; verify dark mode compatibility
- Gmail App (iPhone 15, iOS 17)High mobile usage in Australia; assess touch targets and narrow-width display
- Microsoft Outlook (Android 11)Used by Australian mobile users; check alignment and button visibility on smaller screens
Inspect what affects use
Review the subject and preview text in the inbox list, then open the message. Look for:
- clipped text or buttons at narrow widths;
- columns stacking in an order that changes the meaning;
- an important action conveyed only by an image;
- text, links or a logo losing contrast in dark mode;
- headings or prices wrapping awkwardly;
- footer controls that are hard to find or use.
Compare screenshots with the intended design, but judge whether content remains clear rather than demanding identical pixels. Look for missing or obscured text, unexpected wrapping, colour or contrast changes, alignment and spacing differences, and headings or actions that are hard to find.
Open each test message and activate every link and button. Confirm each control is usable and its destination or action matches its label, and note anything that is difficult to see or use.
If the message relies heavily on images, switch images off in a test inbox. Confirm the remaining text still explains the main offer and action.
Key Elements to Inspect During Email Client Testing
- Clipped text or buttons at narrow widthsEnsure content remains legible on mobile devices with small viewports
- Columns stacking in incorrect orderMaintain logical reading flow—especially important for offers and calls to action
- Critical actions reliant only on imagesAlways include alt text and visible text for accessibility and fallback clarity
- Text or logo contrast loss in dark modeVerify readability against dark backgrounds—critical for ATO and superannuation communications
- Headings or prices wrapping awkwardlyAvoid confusion in pricing or key messages—ensure clarity for GST and discount disclosures
- Footer controls hard to find or useEnsure unsubscribe links and ABN details are accessible on all devices
Record and fix defects
Record the client, device or viewport, setting, affected section and observed problem. For example, note that a button label cannot be read in dark mode on this phone.
Decide whether the message remains understandable and the control usable. A small spacing difference may be acceptable; an unreadable price or hidden action is more serious.
Dark mode needs specific attention. Check the revised design in the affected view rather than assuming a change works everywhere.
Retest the final build
A change to a shared header, button or footer can affect several parts of the email. Refresh previews after material design changes and send a fresh test to the same affected inboxes, using the same device and settings.
After a fix, check the view where the problem appeared and any other views affected by the change. Record the views checked and those still untested; describe observed coverage rather than promising that the template works in every client.
Process for Retesting a Fixed Email Template
- Refresh previews after design changesUpdate shared components like headers, buttons or footers in the email editor
- Send fresh test to affected inboxesUse the same client, device and settings as previous tests for accurate comparison
- Check both the original issue and related viewsA fix in one area may affect other clients—especially those using similar rendering engines
- Record tested and untested viewsDocument coverage clearly—avoid claiming universal compatibility without evidence
