Short answer:
Dark Mode can change how your email signature appears. Use transparent images, strong contrast, and simple design choices to ensure your signature remains readable on both light and dark backgrounds.
Dark Mode is widely used across devices and email clients. It changes the interface from light backgrounds with dark text to darker backgrounds with light text.
However, email signatures do not always adapt perfectly. Some email clients modify colours automatically, while images and logos remain unchanged. This can lead to poor contrast or elements becoming difficult to read.
Because there is no universal way to control how signatures behave in Dark Mode, the best approach is to design your signature with both light and dark backgrounds in mind.
Best practices for Dark Mode
- Use transparent images (PNG)
Avoid solid white backgrounds. Transparent PNGs prevent visible “white boxes” in Dark Mode. - Ensure strong contrast
Use colours that are clearly visible on both light and dark backgrounds. - Avoid dark text in logos
Dark elements can disappear on dark backgrounds. Use lighter colours or alternative logo versions if available. - Keep designs simple
Complex graphics are more likely to lose clarity when colours are inverted or adjusted by email clients.
Improve logo visibility
If your logo contains dark text or elements, they may become hard to see in Dark Mode.
To improve visibility, you can:
- Use a version of your logo with brighter colours
- Add a subtle white or light outline around dark elements
- Ensure the logo works on both light and dark backgrounds
Example of improving logo visibility:
Important when adding outlines
When applying a stroke or outline, place it outside (offset) the logo or text. This prevents unwanted thickness or distortion in the original (light mode) version.
Key takeaway
You cannot fully control how Dark Mode renders email signatures across all clients. Instead, focus on:
- High contrast design
- Transparent images
- Testing in both light and dark mode
This ensures your email signature remains clear, professional, and readable in all environments.
