Text and backgrounds
Check whether text retains enough contrast after color transformation.
All email tools
Email Dark Mode Checker
Check whether your email stays clear in dark mode
Paste HTML to focus on text, background, button, and logo risks after Gmail, Outlook, and Apple Mail color transformations.
Static analysis runs in this browser. Your HTML is not uploaded, and previews block external resource requests.
0 characters
Client simulation
Switch client-rule previews
This is a rule and typical-viewport simulation, not a real inbox screenshot. Test important email in real inboxes.
Paste or load HTML to switch between dark-mode simulations.
What this dark-mode check covers
The checker transforms colors under several client rule sets and groups repeated risks into one actionable report.
Buttons and borders
Find actions that may disappear or blend into their background.
Logos and images
Review transparent logos, icons, and image edges on dark backgrounds.
Client differences
Compare common Gmail, Outlook, and Apple Mail color behavior.
This is a rule-based simulation, not an inbox screenshot
Client versions, operating-system settings, and message content affect the final result. Use this report to locate risk, then run a real inbox test before an important send.
Keep working on this email
Try another free email tool
Each tool works independently. Continue with the same HTML email based on what you need to handle next.
Prepare the code
Open tool Email CSS inliner and optimizer
Move baseline CSS into elements while preserving responsive rules, dark mode, and Outlook conditional comments.
Add the alternative
Open tool HTML email to plain text
Preserve structure, lists, links, and image alt text in a clear, readable plain-text version.
Before inbox testing
Open tool Complete HTML email preflight
Check Gmail clipping, Outlook CSS, dark mode, links, images, and accessibility risks.
Readable by more people
Open tool Email accessibility checker
Check language, image alt text, link names, contrast, headings, and table semantics.
Release rules
Open tool Email release checker
Check variables, test domains, UTM, unsubscribe content, and team publishing rules.
Network verification
Open tool Email link checker
Check link and image URL status, redirects, DNS, TLS, and timeouts.
Email dark mode checker FAQ
Is my HTML uploaded during the check?
No. Color analysis and client-rule simulation run in this browser. Your HTML is not uploaded just to run this check.
Is the preview a real Gmail or Outlook screenshot?
No. It is generated from known color-transformation rules. It is useful for locating risk but does not replace a real send test.
Why does the same email look different across clients?
Apple Mail can honor authored dark styles, while some Gmail and Outlook versions actively invert or replace colors. The resulting email can therefore differ by client.
How can I reduce dark-mode failures?
Keep strong contrast for essential text and buttons, give transparent logos a safe edge or background, and avoid relying on only one light-background and dark-text pairing.
EasyAImail
After the check, finish the complete email beside your inbox
These free tools help locate code and pre-send risks. When you need to understand a message, fill in details, choose a template, and create the complete email, install the Edge or Firefox extension or continue in the full web app.
Get the Edge extension 
Get the Firefox extension