Short answer. Your Amazon book title and subtitle must match what is on your cover, and together they must be fewer than 200 characters. KDP bans words like "free" and "bestselling" and repeated generic keywords in both. Keep the title as printed, and use the optional subtitle to say plainly what the book is and who it is for.
Key points
- The title field holds only the title as it appears on your cover.
- Title plus subtitle must be fewer than 200 characters.
- The subtitle is optional and follows the same rules as the title.
- No "free", no "bestselling", no repeated generic keywords, no other authors' titles or names.
- KDP notes readers are more likely to skim past titles over 60 characters.
- Our Amazon book listing optimization writes the subtitle with the description, keywords, categories and bio.
What are KDP's rules for an Amazon book title and subtitle?
The title field holds only the title as printed on your cover. Title and subtitle together must be fewer than 200 characters. KDP bans promotions like "free", sales rank claims like "bestselling", and repeated generic keywords. Use the optional subtitle to say plainly what the book is.
KDP's Metadata Guidelines say the title field "should contain only the actual title of your book as it appears on your book cover." The subtitle is optional, and KDP says it must follow the same guidelines as the title.
The length rule covers both: "Your title and subtitle together must be fewer than 200 characters."
Which words are not allowed in the title or subtitle?
KDP lists these:
- references to promotions, such as "free";
- references to sales rank, such as "bestselling";
- generic keywords repeated, such as "notebook", "journal", "gifts" or "books";
- unauthorized references to other titles or authors;
- HTML tags.
A book with several stories should say so with a word like "Collection" or "Compilation". Our post on why Amazon KDP rejected my book covers what else gets a book flagged.
How long should a subtitle be?
Shorter than the limit allows. KDP's keywords page says customers "are more likely to skim past long titles (over 60 characters)".
So 200 characters is the ceiling, not the goal. Aim for a title and subtitle a reader can take in at a glance on a phone.
How do I write a subtitle that sells?
Say what the book is, in the words a reader would use. A subtitle works hardest on books where the title alone does not tell you the genre or the promise.
Three tests before you keep one:
- Does it describe the content? KDP wants metadata that matches the book.
- Would a reader search those words? Check them in Amazon search first.
- Is it honest? No claims the book cannot back up.
Here is one we drafted on 13 October 2026 for our own Great Gatsby sample book: "The Great Gatsby (Annotated): Long Island, Summer 1922". The "(Annotated)" label is there because Gatsby is public domain, and KDP wants that label in the title field of an annotated edition. The title is 28 characters and the subtitle 24, so this Amazon book title and subtitle come to 52 characters, under KDP's 60-character skim line and far under 200. It names the setting and the year, which is what a reader browsing classics might search.
The fix we do for this: Amazon book listing optimization. We research and write your subtitle, description, 7 keywords, 3 categories and author bio as text ready to paste into KDP. It costs $149 and takes 5 business days, and we never log in to your account. Send us your book.
Should keywords go in the subtitle?
Only if they truly describe the book. KDP's rules ban repeated generic keywords in the title field, and its keywords page says keywords can carry information "that won't fit in your title and description". So the 7 keyword boxes are the place for search terms. Our post on the KDP 7 keywords shows how to fill them.
Can I change my title or subtitle after publishing?
For a paperback, only briefly. KDP's Timelines page says you can change a paperback's title, subtitle or author name within 72 hours of first publication, after the book is no longer in review. For a Kindle ebook, KDP locks the title after publishing, so a new title means a new edition.
What about public domain books and series?
Both have extra rules. A public domain book must add (Translated), (Annotated) or (Illustrated) to the title field when it qualifies. Public domain and low-content books cannot be set up as a series, and a series title follows the same rules as a book title.
What else do authors ask about a book title and subtitle on Amazon?
Fewer than 200 together.
Yes. KDP says the title field holds the title as it appears on your cover.
No. KDP does not allow references to sales rank in the title or subtitle.
No, it is optional. Use one when the title alone does not tell readers what the book is.
Only within 72 hours of first publication, once the book is out of review.
What should you do next?
Write your subtitle, count the characters of title and subtitle together, and check each word against KDP's banned list. If you would rather have the subtitle and the whole listing written for you, start on our Amazon book listing optimization page.
