Reading Ruler & Color Overlay Online Free

A reading ruler (also called a reading strip or line guide) is a visual aid that highlights one line of text at a time while dimming the rest. It helps readers track text more easily, reducing skipping lines and losing your place.

Color overlays reduce visual stress (also called Meares-Irlen syndrome or scotopic sensitivity) by changing the contrast between text and background. Research shows that for some readers, specific colors make text appear more stable and comfortable to read.

There is no single best color — it varies by individual. Yellow and blue are the most commonly preferred. Try each option and choose the one that makes text feel most comfortable and stable to your eyes.

No. Reading rulers and overlays help anyone who finds on-screen reading tiring, including people with visual stress, ADHD, learning differences, or those who simply read large amounts of text. Many neurotypical readers also benefit.

Yes. The tool is fully responsive. On mobile, the ruler follows your finger touch on the reading area. You can also lock the ruler in place.

Yes. Paste any text — articles, homework, emails, ebooks, study notes — into the text area. The tool renders it with your chosen settings for comfortable reading.