HTML tags KDP accepts in a book description
KDP’s description field takes a small set of HTML tags, and the formatter only writes those. Anything else is converted (<strong> → <b>, <h1> <h2> <h3> → <h4>, <div> → <p>) or removed with its text kept, and every tag is closed.
| Tag | What it does | In the formatter |
|---|---|---|
<br> | Line break | Shift + Enter |
<p> | Paragraph | Enter starts a new one |
<b> | Bold | Bold |
<em> | Emphasis (italic) | Kept in HTML mode |
<i> | Italic | Italic |
<u> | Underline | Underline |
<h4> | Largest heading | Heading (H4) |
<h5> | Medium heading | Subheading (H5) |
<h6> | Smallest heading | Small heading (H6) |
<ol> | Numbered list | Numbered list |
<ul> | Bulleted list | Bulleted list |
<li> | List item (inside <ul> or <ol>) | Each line of a list |
The 4,000-character limit counts the HTML
KDP’s editor counts every character in the description, HTML tags included. “test” is 4 characters; “<b>test</b>” is 11. A list with ten short items spends about 99 characters on tags alone, so heavy formatting eats into the room left for words. The counter above measures the exact HTML you will paste.
Double or multiple spaces between words don’t show on the Amazon detail page, so the formatter collapses them to one space instead of counting them.
What KDP doesn’t allow in a description
According to KDP Help, a description can’t include:
- Pornographic, obscene or offensive content
- Phone numbers, mailing or email addresses, or website URLs
- Reviews, quotes or testimonials, and requests for customer reviews
- Advertisements, watermarks or promotional material
- Time-sensitive information, such as dates of promotional tours, seminars or lectures
- Availability, price or other ways to order
- Spoilers
- Unicode emojis
- Keywords or book tag phrases
The formatter flags links, email addresses, phone numbers, prices, emojis, star ratings and review requests it finds. It can’t judge spoilers or tone, so read the preview before you publish.
Fixing KDP description errors
“Description may not contain invisible characters” and “Please fix the highlighted issue” usually mean hidden characters or unsupported HTML came in with a copy-paste. KDP suggests typing the description by hand or checking the source. Pasting into the formatter handles both causes: it strips invisible characters and rebuilds the HTML with supported tags only. If bold or a heading runs on too far in KDP, a tag was left open; the formatter closes every tag.
Where to paste it in KDP
On your Bookshelf, click the ellipsis button (⋯) next to the book and select Edit Details. Under Description, click the Source button, paste the HTML, then switch back to check the formatting. Click Save and Continue, then Publish at the bottom of the Pricing page.
Planning the rest of the book? Estimate its length with the word count to page count calculator, then check the royalty at your list price.