Why Your Eyes Feel Worse After Switching to Dark Mode

Dark mode isn't easier on everyone's eyes. If text looks blurry, glows or tires you faster after switching, there are real reasons, and most of them can be fixed with a few settings.

Why dark mode can feel worse

• Halation with astigmatism. People with astigmatism often see light text on a dark background spread or glow at the edges, which makes letters fuzzy. Astigmatism is common, so this affects many people.
• Wider pupils. A dark screen lets your pupils open wider, which reduces how sharply your eye focuses. Dark text on a light background keeps pupils smaller and text crisper.
• Too much contrast. Pure white text on pure black is harsh and makes halation worse.
• The wrong room. In a bright room, a dark screen makes your eyes keep adjusting between the screen and the surroundings.

Reading research has generally found that, for most people in normal lighting, dark text on a light background is a little easier to read. Dark mode's real strengths are less glare at night and comfort for some light-sensitive people.

Make dark mode easier to read

• Dark gray, not black. A background around #1a1a1a to #222 is gentler than pure black.
• Off-white text, not pure white.
• Slightly larger text and a regular or medium weight. Thin fonts break up in dark mode.
• Lower your screen brightness when using dark mode at night.
• Keep a light on in the room.

Modern Dark Mode turns white pages into dark gray rather than pure black, and its contrast, brightness and sepia sliders let you soften the result further. If text still glows, lower the contrast a little.

When light mode is the better choice

• Daytime reading in a bright room.
• Long documents, if you have astigmatism and notice blur in dark mode.
• Detailed work where text must be crisp.

Many people do well with light mode by day and dark mode in the evening. See how to schedule dark mode by sunrise and sunset.

Other ways to reduce eye strain

• A warmer screen in the evening. Blue Light Filter tints web pages amber on a schedule.
• Larger text and better line spacing. See how font size affects reading fatigue.
• Regular breaks: look at something 20 feet away for 20 seconds every 20 minutes.

See an eye doctor if it continues

Tired eyes, blur or headaches that don't improve with these changes can be a sign of uncorrected astigmatism or another vision problem. Glasses for screen distance often help more than any setting.