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Bionic reading

Bold the leading part of each word so your eyes move through text faster.

Input
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Output

Bionic reading

Bionic reading bolds the first part of every word and leaves the rest in normal weight, so your eyes only need to fixate on the leading letters and can glide through the remainder guided by context. The technique shows up in speed-reading apps and accessibility tools because it reduces the effort of decoding long paragraphs, articles or study notes. Paste any block of text and the result updates as you type.

The bold-portion slider controls how much of each word gets bolded — a lower value bolds just the first letter or two for a light touch, a higher value bolds most of the word for a stronger effect. Minimum word length skips words too short to need the boost, and skipping short conjunctions and prepositions additionally leaves common words like "the", "and" or "of" untouched, since bolding them adds visual noise rather than reading speed. Pick the output format that matches where you'll paste the result: HTML with <strong> tags for web pages, Markdown with double asterisks for editors and static sites, or Unicode bold characters that render as bold in plain-text fields with no markup support, such as chat apps or bare note-taking tools.

Line breaks, paragraph spacing and punctuation are left exactly as typed — only the letters inside words are touched. Words with diacritics (á, č, ő, ł and the like) are measured and split correctly by their actual letters, not raw bytes; the Unicode format bolds plain Latin letters and digits but has no bold variant for accented letters, so those pass through unstyled inside an otherwise bold word. Turn on number highlighting to apply the same bold-start treatment to standalone digits.

Everything runs locally in your browser — the text you paste is never uploaded or stored anywhere. Copy the result, download it as a .txt file, or send it straight to another tool's input to keep editing.

FAQ

What is bionic reading and does it actually help me read faster?
Bionic reading bolds the first part of each word so your eyes recognize it faster and glide across the rest using surrounding context. Many readers find it reduces fatigue on long text, though the effect varies from person to person.
Which output format should I use?
Use HTML if you're pasting into a web page or CMS, Markdown for editors and static-site generators that render **bold** text, and Unicode bold characters when you need the bolding to show up as-is in plain text such as chat messages or notes apps.
Why are some short words left unbolded?
Words shorter than the minimum length, plus common conjunctions and prepositions like "the" or "and" when that option is on, are skipped on purpose — bolding tiny function words adds visual noise without helping your eyes move faster.
Does the Unicode format support accented letters?
No. Mathematical Unicode bold only covers plain Latin letters A–Z and digits 0–9, so accented characters such as á, č or ő inside a bolded word stay in their normal weight. Use the HTML or Markdown format if every character needs to appear bold, diacritics included.
Is my text uploaded anywhere?
No. Bionic reading runs entirely in your browser — your text is never sent to a server.