Bionic Reading Converter
Bolds the first half of every word so your eye can lock onto the start and read 30–40% faster.
What is bionic reading?
Bionic Reading is a typographic technique that bolds the first part of each word — the so-called artificial fixation point. Your eye anchors on the bold portion, your brain auto-completes the rest from context, and you can read meaningfully faster without losing comprehension.
The technique was popularized by Renato Casutt in 2022 and went viral after Twitter and Reddit users tested it on books and articles. Anecdotal speedups range from 15% to 50%; controlled studies show smaller but real gains, especially for longer passages.
How to use this converter
- Paste the text you want to convert in the box above. The conversion is instant — no button press needed.
- Choose a bold ratio — 50% is the default and most balanced. Choose 40% for a lighter effect on long-form reading; 60% for heavier emphasis on dense material.
- Read the converted text in the preview panel below the toolbar.
- Click Copy as HTML to copy the markup with
<b>tags — paste into any web editor, email, or document that supports HTML.
When bionic reading helps
- Long-form articles you need to skim. The bold anchors let you process 1.5× the text in the same time.
- Dense reference material. Manuals, legal text, and academic abstracts benefit from forced fixation points.
- Reading with ADHD or dyslexia. Many users with attention or word-decoding challenges report easier comprehension. (This is anecdotal; effects vary by individual.)
- Foreign-language text. When learning a new language, bold prefixes help recognize root forms faster.
When bionic reading does NOT help
- Code, math, and tables. Bionic conversion adds noise without benefit when the content is symbolic.
- Poetry, lyrics, and literary prose. The aesthetic of the original is part of the meaning.
- Already-skimmed content. If you're rereading something you know well, you'll skip the bold cues anyway.
Frequently asked questions
Is bionic reading actually backed by research?
Lightly. Renato Casutt's original claims were marketing-strength; subsequent academic studies (e.g., Bristol University 2022) found small or null effects in lab conditions. Many users report subjective gains in real-world reading. Try it on a long article and decide for yourself.
Does it work for languages other than English?
Mostly yes — any space-separated alphabet language (Spanish, French, German, Italian) works. Languages without word boundaries (Chinese, Japanese without kanji) won't benefit because the algorithm can't find prefix boundaries.
Why does the converter use 50% by default?
50% (round up) is the most studied ratio and the one Casutt's original demos used. 40% is gentler and works well on already-easy text; 60% is more emphatic and helps on dense paragraphs.
Can I save the bolded text as a PDF or document?
Click 'Copy as HTML' then paste into a Word doc or Google Doc — the bold formatting carries over. Print to PDF from there. Or paste into any rich-text email and your recipient sees the bionic version.