YouTube Text Formatter: Bold, Italic & Strikethrough
Make YouTube bold text for comments, titles and descriptions. Style it once and get both versions: YouTube's own comment tags and Unicode bold for the places tags don't reach, like video titles.
Formats right in YouTube's comment box. Also works on LinkedIn, X, Facebook, Threads & Bluesky.
The same text with YouTube's own tags. Paste it into a comment and YouTube shows real bold, italic and strikethrough.
Short version · Updated October 2026
To bold text in a YouTube comment, wrap it in asterisks: *like this*. Underscores give italics and hyphens give strikethrough. YouTube Help documents all three tags, and they render once the comment is posted.
Video descriptions get bold, italic and strikethrough from the formatting options in YouTube Studio. Titles, channel names and the channel description have no formatting at all, so Unicode characters such as 𝗯𝗼𝗹𝗱 and 𝘪𝘵𝘢𝘭𝘪𝘤 are the only way to style them. The formatter above makes both versions from the same text.
Where YouTube supports bold, italic and strikethrough
YouTube treats each text field differently, and most guides get at least one of them wrong. Here's what each field does in October 2026, with the source for every limit.
| Field | Native formatting | How | Length limit |
|---|---|---|---|
| Comments and replies | Yes: bold, italic, strikethrough | *bold* _italic_ -strike- | 10,000 characters (widely reported, not published by YouTube) |
| Posts (Community tab) | Yes, same tags (reported by creators) | Same tags as comments | Not published |
| Video and Shorts descriptions | Yes: bold, italic, strikethrough | Formatting options under the description box in YouTube Studio; on mobile, highlight text | 5,000 (characters per YouTube Help, bytes per the Data API) |
| Video and Shorts titles | No | Tags show as typed. Use Unicode | 100 characters; no < or > |
| Channel description (About) | No | Use Unicode | 1,000 characters |
| Channel name, playlist titles | No | Use Unicode | Varies |
Sources: YouTube Help, “Post & interact with comments” and “Tips for video descriptions”; YouTube Data API reference for the videos and channels resources. Checked 15 October 2026.
Where the second column says no, Unicode is the only way to get a styled look. It also works in the fields that have tags, which is useful when you want a style YouTube doesn't offer, such as underline, monospace or small caps.
YouTube comment markup or Unicode: which one to use
Both look bold on screen. Underneath they're different things: markup is plain text with tags that YouTube styles when it shows the comment, Unicode is a different set of letters. That difference decides where each one works.
Comment markup *bold* | Unicode 𝗯𝗼𝗹𝗱 | |
|---|---|---|
| Works in | Comments, replies, posts | Every field, titles and channel About included |
| Styles | Bold, italic, strikethrough and their combinations | 30+ (underline, monospace, script, small caps and more) |
| While you type | You see the tags; the style appears after posting | Looks styled immediately |
| Search | Plain letters underneath, so the words stay searchable | Different characters; search may not match the plain word |
| Screen readers | Read normally | Some read letter by letter or skip it |
| Copied off YouTube | Turns back into asterisks and underscores | Keeps its look anywhere |
So: tags in comments, Unicode for titles and the About section, and plain letters for any word you want people to find through search. The YouTube comment markup box under the preview converts your styled text into tags for you.
How styled letters count against YouTube limits
YouTube Help gives the description limit as 5,000 characters, while the YouTube Data API defines it as 5,000 bytes of UTF-8. Plain Latin letters take 1 byte each. Unicode styles take 3 or 4. If YouTube counts bytes, a styled description runs out much sooner. Measured from this tool's own output:
| Style | Example | Bytes per letter | Letters in 5,000 bytes |
|---|---|---|---|
| Plain | YouTube | 1 | 5,000 |
| Bold | 𝗬𝗼𝘂𝗧𝘂𝗯𝗲 | 4 | 1,250 |
| Italic | 𝘠𝘰𝘶𝘛𝘶𝘣𝘦 | 4 | 1,250 |
| Bold italic | 𝙔𝙤𝙪𝙏𝙪𝙗𝙚 | 4 | 1,250 |
| Strikethrough | Y̶o̶u̶T̶u̶b̶e̶ | 3 | 1,666 |
| Small caps | ʏᴏᴜᴛᴜʙᴇ | 3 | 1,666 |
| Monospace | 𝚈𝚘𝚞𝚃𝚞𝚋𝚎 | 4 | 1,250 |
Comment tags cost 2 characters per styled phrase (the opening and closing tag), whatever its length. For long descriptions, style the section labels and keep the body plain.
How to Use the YouTube Text Formatter
Write your comment, title or description in the editor, select the words to style and pick a style. The preview shows the comment the way YouTube draws it, and the box under the preview gives you the same text with YouTube's tags.
Type or paste
Enter the comment, title or description in the editor above.
Select and style
Highlight words and click Bold, Italic, Strikethrough or a font.
Pick your version
Copy the Unicode text, or Copy markup for a comment.
Paste into YouTube
Comments and posts take either. Titles need the Unicode text.
The Unicode version is made of characters from the Mathematical Alphanumeric Symbols block (U+1D400 to U+1D7FF) plus the combining long stroke overlay (U+0336) for strikethrough. They're ordinary text, so they paste into any YouTube field and show the same on desktop, the YouTube app and smart TVs, as long as the device's font has the glyphs.
YouTube Font Styles
8 styles in this free formatter. The Chrome extension has 20+ more.
𝗛𝗲𝗹𝗹𝗼 𝗪𝗼𝗿𝗹𝗱
Bold
A title keyword or the first line of a pinned comment.
𝘏𝘦𝘭𝘭𝘰 𝘞𝘰𝘳𝘭𝘥
Italic
Song names, quotes and asides in a description.
𝙃𝙚𝙡𝙡𝙤 𝙒𝙤𝙧𝙡𝙙
Bold Italic
One word you want nobody to miss.
H̶e̶l̶l̶o̶ ̶W̶o̶r̶l̶d̶
Strikethrough
Old prices, fixed mistakes, crossed-off lists.
H͟e͟l͟l͟o͟ ͟W͟o͟r͟l͟d̲
Underline
Something YouTube has no tag for at all.
𝙷𝚎𝚕𝚕𝚘 𝚆𝚘𝚛𝚕𝚍
Monospace
Code snippets and settings in tech tutorials.
𝓱𝓮𝓵𝓵𝓸 𝔀𝓸𝓻𝓵𝓭
Script
A channel About section with some personality.
ʜᴇʟʟᴏ ᴡᴏʀʟᴅ
Small Caps
Section labels like ᴛɪᴍᴇꜱᴛᴀᴍᴘꜱ or ʟɪɴᴋꜱ.
Where Styled Text Helps on YouTube
A comment section or a description is a wall of same-looking text. A few styled words give a reader something to stop on.
Pinned comments
Bold the one line you want viewers to act on: the link, the fix, the timestamp.
Descriptions that scan
Styled section labels split chapters, links and credits into readable blocks.
Titles with a stress
One Unicode bold word can carry a title. Keep the search keyword plain.
Channel About text
The About box has no formatting at all, so Unicode is the only option there.
Search
Styled letters are different characters, so search may not match them to the plain word.
Screen readers
Some read Unicode bold letter by letter or skip it. YouTube’s comment tags don’t have that problem.
Description budget
A bold letter is 4 bytes of UTF-8, and the API limit for descriptions is 5,000 bytes.
Style Comments Without Leaving YouTube
The editor here is fine for a title or a one-off. If you comment a lot, the free Post Formatter Chrome extension puts the toolbar inside YouTube's comment and reply box, so you select a word and style it where you type.
- Inline toolbar in the comment box on youtube.com
- 30+ styles, including the 8 on this page
- Lists, symbols and emoji from one menu
- Shortcuts: Ctrl+B, Ctrl+I, Ctrl+U
- Smart Paste keeps bold and italics from Google Docs or Word
- Same toolbar on LinkedIn, X, Facebook, Threads, Bluesky and Pinterest
YouTube Formatting FAQ
Updated October 2026
How do you bold text in a YouTube comment?
Why is my YouTube comment formatting not working?
Can you make a YouTube video title bold?
Can you bold text in a YouTube description?
Do Unicode letters use up more of the description limit?
Does this work in YouTube posts and Shorts?
Is this YouTube text formatter free?
Formatters for Other Platforms
Bluesky Text Formatter
Bold and italic for Bluesky, with a 300-grapheme counter.
X (Twitter) Text Formatter
Bold and fancy fonts for posts, replies and your X bio.
Facebook Text Formatter
Bold, italic and Unicode fonts for posts and comments.
Threads Text Formatter
Style Threads posts, replies and your bio.
Bold Text Generator
Six bold Unicode styles to copy in one click.
Post Formatter Extension
The toolbar inside YouTube, LinkedIn, X and more. Free.
YouTube comment formatting: what you type and what shows
*great video*_the ending_-old intro-old intro*_must watch_** not bold *Keep punctuation outside the closing tag (
*done*!) and leave a space or line start before the opening one. Tags don't work in titles, descriptions or your channel's About text.