How to Bold Text on LinkedIn (and When Not To)

Short answer: a LinkedIn post has no bold button, on desktop or in the app. To bold words in a post, paste the draft into the free LinkedIn post formatter, select the words, click Bold, then Copy post and paste it into LinkedIn. The bold is made of Unicode letters that look bold, so use it on a few words only: screen readers and search can miss them, and each bold letter takes 2 of your 3,000 characters in PostBoost.

Where LinkedIn has real bold, and where it doesn't#

LinkedIn's help page for articles says the editor lets you "change the style, bold or italicize any text, add ordered or unordered lists, add blockquotes, or add a divider". That is real formatting, and it is accessible. Anything else on LinkedIn is plain text. Wrapping a word in asterisks does nothing: LinkedIn does not read Markdown, so *word* shows the asterisks.

If a post needs headings and several bold passages to be readable, it is probably an article. Write it as one and share it in a short post.

How to bold text in a LinkedIn post#

1. Open the LinkedIn post formatter and write or paste your post. Line breaks are kept exactly as you type them.
2. Select the word or phrase you want to stand out and click Bold (or Italic, or Bold italic).
3. Check Feed preview (approximate fold) under the editor. It shows roughly what readers see before "…see more".
4. Click Copy post and paste it into the LinkedIn post box. To schedule it instead, click Schedule this: the post opens as a draft in PostBoost, where you pick your LinkedIn profile or Page and a time.

The same steps work on a phone: open the formatter in your mobile browser, tap Bold, copy, and paste into the LinkedIn app. The formatter runs in your browser, and your text stays on your device until you click Schedule this.

The fancy text generator has more styles (sans bold, script, monospace and others), but for LinkedIn, plain Bold is the safest: most phones and computers have a font for it, while rarer styles can show up as empty boxes on older devices.

What bold letters cost#

A bold "𝐁" is not a bold B. It is a different character, U+1D400 MATHEMATICAL BOLD CAPITAL B, from a Unicode block meant for maths. The Unicode Standard is direct about it: these characters "should not be used to represent styling of nonmathematical text". Here is what that means in practice.

Screen readers. A reader can't tell the letters are an "A" or a "B" in bold. Per Axbom recorded a screen reader going "completely silent" on a bold-italic phrase in the middle of a sentence. Other readers announce each letter by its Unicode name. If your key point is in bold, some people never hear it.

Search. Search compares characters, and 𝐦𝐚𝐫𝐤𝐞𝐭𝐢𝐧𝐠 is not the word marketing. Keep keywords, product names, hashtags and @mentions in plain text so people searching for them find the post.

Characters. Bold letters sit outside the basic range of Unicode, so each one takes two UTF-16 units. PostBoost counts LinkedIn posts in UTF-16 units, as JavaScript does, and Buffer's developer guide says LinkedIn counts the same way:

Spaces stay plain, so they still count 1. A post written entirely in bold reaches the 3,000 limit at about 1,500 letters. The LinkedIn character limit guide covers the rest of the count.

Letters without a bold twin. Unicode's maths bold set covers A–Z, a–z and 0–9 only. Accented letters such as é, ü or ğ and all punctuation stay plain, so a bold "Café" comes out as 𝐂𝐚𝐟é. Check names and non-English words in the preview before you post.

Where bold actually helps#

Use bold where a reader scanning the feed needs a signpost, and nowhere else. A good rule: no more than one bold item per screen, and never a whole sentence.

Before:

𝐖𝐞 𝐜𝐮𝐭 𝐨𝐮𝐫 𝐨𝐧𝐛𝐨𝐚𝐫𝐝𝐢𝐧𝐠 𝐟𝐫𝐨𝐦 𝟏𝟒 𝐝𝐚𝐲𝐬 𝐭𝐨 𝟑.
𝐇𝐞𝐫𝐞 𝐢𝐬 𝐰𝐡𝐚𝐭 𝐰𝐞 𝐜𝐡𝐚𝐧𝐠𝐞𝐝 𝐚𝐧𝐝 𝐰𝐡𝐲 𝐢𝐭 𝐦𝐚𝐭𝐭𝐞𝐫𝐬.

After:

We cut our onboarding from 14 days to 3.

𝐖𝐡𝐚𝐭 𝐰𝐞 𝐜𝐡𝐚𝐧𝐠𝐞𝐝
• One welcome call instead of four emails
• A sample project ready on day one

𝐖𝐡𝐚𝐭 𝐝𝐢𝐝𝐧'𝐭 𝐰𝐨𝐫𝐤
• Video tutorials nobody opened

The hook stays plain, so everyone can read it, search can find it, and it fits the roughly 140 characters the app shows before "…see more". The bold is on two short section labels that someone using a screen reader can lose without losing the point. The bullets come from the formatter's • Bullet list button.

Bold from code or an AI assistant#

The formatter is also a free API and MCP tool, so a script or an assistant can style text the same way. No account or token is needed:

curl -X POST https://postboost.co/app/api/tools/linkedin-post-formatter \
  -H 'Content-Type: application/json' \
  -d '{"text":"What we changed","style":"bold"}'

The response holds the styled text, its count against the limit of 3,000, and the preview before "…see more". The style applies to the whole text you send, so call it for a label, not the full post. In an AI assistant connected to PostBoost's free tools MCP server (https://postboost.co/mcp/tools), the tool is format-linked-in-post. The request fields and SDK examples are in the formatter API docs.

Schedule the post#

Click Schedule this in the formatter, or paste the finished text into the PostBoost composer, and pick your LinkedIn profile or Page. The bold letters are ordinary text to PostBoost, so they publish exactly as you see them, and PostBoost counts them the same way the formatter does. Over the limit, the composer shows "Maximum of 3000 characters allowed." and won't schedule a post over the limit. The post checker runs the same LinkedIn checks in your browser, with the 140-character fold, before you open the app. New to PostBoost? Create a free account.