Bold the first letters of every word and copy the result as HTML or Markdown. Nothing leaves your browser.
A bionic reading converter makes the first letters of every word bold, so the rest of the word looks lighter. This one counts the letters in each word and bolds a share of them, rounded up and never fewer than 1. Low bolds about a third, Medium about half and High about two thirds. For example, Hello world at Medium becomes Hello world with Hel and wor in bold. In Markdown that is **Hel**lo **wor**ld, and in HTML the same parts sit inside b tags. A one-letter word is bold in full. Punctuation and spaces are kept as typed, and the apostrophe and hyphen are not counted as letters. Accented letters stay with their marks, so café is bolded as caf plus é at Medium. Other alphabets such as Cyrillic work the same way.
A word with an apostrophe is one word: don't has 4 letters, so Medium bolds do and leaves n't plain. A hyphenated word is handled in parts, so each part gets its own bold start: well-known becomes we in bold, ll-, kno in bold, wn. This makes both halves easy to find. Numbers are left plain by default, including 2026, 3.14, 1,000 and 2026-10-15, because bolding half a number makes it harder to read. Turn off Leave numbers alone to give them a bold start too. Words that mix letters and digits, such as abc123 or 3rd, are treated as words. The count of words changed and numbers left alone is shown above the result.
The HTML box has b tags around the bold parts, and the characters & < > in your text are escaped, so a text with a less-than sign still displays as typed. Line breaks stay as plain line breaks, which a browser shows as spaces, so put the HTML in a pre element or use the CSS rule white-space: pre-line to keep the lines. The Markdown box wraps the bold parts in two asterisks and puts a backslash before *, _, ` and \ so that they show as typed. Both outputs read as your original text once the tags or asterisks are removed. Text up to 500,000 characters is handled.
This tool makes no claim that it does. Research on whether bold word starts speed up reading is mixed: some readers like the look and find it easier to keep their place, and others find it no faster or more distracting. Try it on a page you read often and compare it with the plain text. Bionic Reading is a trademark of Bionic Reading AG. This tool is not affiliated with or endorsed by it, and the phrase is used here only to name the technique people search for. The text is processed in your browser, in this tab. It is not uploaded, saved or put in the page address.
Paste your text and leave the strength on Medium. For Hello world it gives Hel and wor in bold, 3 of 5 letters each, because the half is rounded up. Copy the HTML box for a web page or the Markdown box for a document that supports Markdown.
Not directly, because the boxes contain tags or asterisks as plain text. Paste the HTML into an HTML file and open it in a browser, then copy the rendered page into your document. The Markdown box suits tools that read Markdown, such as notes apps.
The share of each word that is bold: about a third, a half or two thirds of its letters, rounded up. A 6-letter word gets 2, 3 or 4 bold letters. A 1-letter word is always bold in full.
Numbers such as 2026, 3.14 and 1,000 are left plain by default because half a number is hard to read. Turn off Leave numbers alone and they get a bold start like words.
Research on this is mixed, and this tool does not promise a gain. Some people find the bold starts help them keep their place; others read at the same speed or find it distracting. Compare it with plain text on a page you know.
No. The text is processed in your browser, in this tab, and no server receives it. Your choices, such as the strength, are saved in this browser, but the text is not. Google Analytics counts visits, results and copy presses, never the text.