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Preview of Plainsight: Dyslexia Font & Reading Ruler

Plainsight: Dyslexia Font & Reading Ruler by Stover

Make any website easier to read. Dyslexia-friendly fonts, adjustable letter and line spacing, colour overlays, reading rulers, dark mode, reader mode and read-aloud — for dyslexia, ADHD, low vision and visual stress. Free, no account, nothing paywall

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About this extension
Make any website easier to read. Plainsight gives you dyslexia-friendly fonts, adjustable letter and word spacing, colour overlays, reading rulers, real dark mode, reader mode and read-aloud — for dyslexia, ADHD, low vision, migraine and visual stress.

Free. No account. No ads. Nothing paywalled. Nobody should have to pay to read a web page.

TEXT AND SPACING
· Seven typefaces: OpenDyslexic, Lexend, Atkinson Hyperlegible, Verdana, Georgia, system sans and Comic Sans — all bundled, so no font server sees your browsing
· Sliders for text size, letter spacing, word spacing, line height and paragraph spacing
· Cap line length so your eye never loses its place
· Bolder text, ragged-right alignment, and an ALL-CAPS undo

COLOUR AND CONTRAST
· Nine page themes: cream, sepia, mist, mint, rose, slate, dark and high contrast, plus a custom colour picker
· Eight colour overlays with adjustable strength — the digital version of a coloured reading sheet, for glare and visual stress
· Two dark mode engines: Smart recolours the page properly, Invert is the blunt fallback for stubborn sites
· Alternating paragraph shading, link emphasis, heading emphasis

READING RULERS AND FOCUS
· Three rulers: a translucent band, a thin underline, or a spotlight that dims everything except your line
· Adjustable height, colour, opacity and dimming — plus keyboard mode, driven by the arrow keys
· Hide sidebars, comments, promos, newsletter popups and social bars
· Stop animation, carousels and autoplay
· Bionic-style bold word beginnings, and syllable breaks for long words

READER MODE AND READ-ALOUD
· Strip any article to clean text with your typography applied, plus a reading time estimate
· Listen to any page or selection, with word-by-word highlighting in reader mode
· Adjustable speed, pitch and voice, using your browser's own voices — works offline, no text uploaded anywhere
· Optional double-click dictionary with pronunciation

PER-SITE SETTINGS
Give any website its own configuration. Cream paper and a reading ruler on news articles, untouched on your email, high contrast on your course site. Switch the popup to "This site" and your changes apply there only.

ONE-CLICK PROFILES
Seven starting points that configure a dozen settings at once: Dyslexia, ADHD Focus, Low Vision, Migraine & Light Sensitivity, Visual Stress / Irlen, Language Learner, and Night Reading. Everything stays adjustable afterwards.

AN HONEST NOTE ABOUT THE RESEARCH
Most reading extensions sell dyslexia fonts as a treatment. The evidence does not support that, and you deserve to know it.

Controlled studies have repeatedly found that OpenDyslexic does not improve reading speed or accuracy compared with ordinary fonts like Arial. What does hold up is increased letter and word spacing, shorter lines, reduced contrast, and text-to-speech.

So Plainsight ships the fonts — plenty of people genuinely prefer them, and preference is a real reason to use something — but makes the evidence-backed settings the defaults. The settings page explains what the research shows for every feature, including where it is weak, with the studies named.

This is not medical advice. If reading is a persistent struggle, an assessment from a specialist teacher, optometrist or educational psychologist will tell you far more than any browser extension.

PRIVACY
Installing an accessibility add-on can reveal something private about you. Good reason for it not to phone home.
· No account, no analytics, no telemetry, no ads
· Settings stay in your browser's own storage
· Fonts are bundled, so no font CDN sees the sites you visit
· Browsing history and page content are never read, stored or transmitted

One possible network request, only if you switch it on: the optional double-click dictionary sends the single word you clicked to dictionaryapi.dev, with no cookies and no referrer. It asks permission first and is off by default.

KEYBOARD SHORTCUTS
Alt+Shift+P on or off · Alt+Shift+R cycle the ruler · Alt+Shift+O reader mode · Alt+Shift+S read aloud · Esc to close reader mode. All remappable.

GOOD TO KNOW
Some sites resist restyling. Smart dark mode will not win against every page built with inline styles, which is why the Invert engine exists. Google Docs draws text to a canvas, so font changes cannot reach it — reader mode and read-aloud still work. Clutter removal uses pattern matching and will occasionally hide something you wanted, which is why it is a toggle. The switch at the top of the popup turns everything off instantly.

CREDITS
Fonts under the SIL Open Font License: Atkinson Hyperlegible by the Braille Institute of America, Lexend by the Lexend Project, OpenDyslexic by Abbie Gonzalez. Definitions from dictionaryapi.dev.

Plainsight is free and open source.
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Required permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
1.0.0
Size
369.97 KB
Last updated
9 days ago (Aug 14, 2026)
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