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Bionic Reading Converter

FREE

Bold the start of each word as rich text or HTML

Free · No sign-up required
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What the bionic reading converter does

Bionic reading bolds the first few letters of each word so the eye can fixate on the emphasised fragment and let the brain complete the rest. Paste text and the converter produces the bolded version as rich text you can copy into a document, an email or a note, and as HTML for a web page. Some readers find it lets them move through text faster or with less effort, particularly on screens; the evidence is mixed, and the tool lets you try it on your own material. Runs in your browser.

How the emphasis is applied

Input: Reading is the process of taking in the sense of letters and symbols. Output: **Rea**ding **i**s **th**e **pro**cess **o**f **tak**ing **i**n **th**e **sen**se **o**f **let**ters **an**d **sym**bols. Rule: bold roughly the first half of each word (rounded up), minimum one letter. 1–2 letters → 1 bold 3–4 letters → 2 bold 5–6 letters → 3 bold 7+ → about half

The bolded fragment acts as a fixation point. Skilled readers already recognise most words from their opening letters and overall shape; the emphasis is meant to make that shortcut explicit and consistent.

What the research says

  • The method was introduced commercially in 2022 and spread through browser extensions and reader apps.
  • Independent tests (including a 2,000-reader study by Readwise in 2022) found no significant improvement in reading speed or comprehension on average; some readers were slightly faster, some slower.
  • Individual reports of benefit are common, especially from people with ADHD or who find long screen text tiring; controlled evidence for these groups is limited.
  • Claims that it helps dyslexia are not supported by dyslexia research organisations, which point to font, spacing and line length as better-evidenced adjustments.

The honest summary: it is a preference, not a proven accelerator. Try it on a page you need to read anyway and keep it if it helps you.

Where to use the output

DestinationHow
Google Docs, Word, Notion, Apple NotesCopy the rich-text output and paste; bold is preserved
EmailPaste rich text into the composer
Web page or CMSPaste the HTML output (<b> tags)
MarkdownConvert the HTML's <b> to ** manually or use the Markdown tools
Plain-text fieldsNot possible — bold needs formatting support

Accessibility and readability alternatives

If the goal is easier reading rather than the bionic style specifically, changes with stronger evidence include: a larger font (16–18 px body), a line length of 50–75 characters, line spacing of 1.4–1.6, generous paragraph breaks, a clean sans-serif or a font designed for readability, high contrast, and reduced screen brightness in the evening. For dyslexic readers, letter spacing and avoiding italics help more than emphasis patterns. The bionic conversion can be combined with any of these.

Frequently asked questions

Does it work for languages other than English?

It applies the same first-letters rule to any space-separated script (most European languages). Scripts without spaces between words (Thai, Chinese, Japanese) are not segmented and will not convert meaningfully.

Can I change how many letters are bolded?

This tool uses a fixed rule (about half of each word). Extensions and apps often offer a fixation slider; adjust in those if you want a lighter or heavier effect.

Why do some words look entirely bold?

One- and two-letter words get one bold letter, which for 'a' or 'I' is the whole word.

Will it help me read faster?

Maybe, maybe not — averaged across readers, studies show no gain. Test it on yourself: time a page normally and a comparable page converted.

Is bionic reading trademarked?

The name is associated with a Swiss company that sells an API and apps. The technique of bolding word beginnings is not protected; this tool implements the general idea.

Is my text uploaded?

No. Conversion runs in your browser.

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