How to Choose KDP Keywords: Filling Your 7 Keyword Fields

What KDP keywords do

When you publish on KDP, you can enter up to 7 keywords or short phrases. Readers never see them. They give Amazon's search more information about your book, alongside your title, subtitle, description, and categories. Good keywords help your book appear for searches that the visible metadata does not already cover.

Keywords will not make an unsuitable book rank for a popular term. They help a relevant book get matched to the searches its readers make. Relevance comes first.

The 7 fields and the character limit

Each of the 7 fields accepts a limited number of characters. This site's tools are configured for 50 characters per field, including spaces. KDP's interface shows the current limit as you type, so verify it there, since Amazon can change it. Figures here were last checked in October 2026.

A field can hold one phrase or several related phrases separated by spaces. Many authors use each field for a group of related search terms so that the space is used fully. Commas and quotation marks are not needed.

Phrases vs single words

Readers search in phrases such as "cozy mystery with recipes" or "anxiety workbook for teens". Entering natural phrases in the order people type them is the safest approach, because it matches real searches directly.

Some authors instead fill fields with lists of separate words, hoping Amazon will combine them into many phrases. How Amazon combines words across fields is not published, so the more reliable choice is to write phrases that make sense on their own and avoid filling space with unrelated single words.

• Use specific phrases. "Victorian ghost story novella" tells search more than "ghost book".
• Cover different angles: subgenre, setting, character type, theme, audience, and occasion (for gift books).
• Avoid repeating the same word across many fields. Repetition uses space without adding new matches.
• Plural and singular forms are often treated similarly, so you rarely need both.

What not to include

KDP publishes metadata guidelines that set out what keywords may contain. Breaking them can lead to your book being blocked or your keywords being ignored. In general terms, avoid:

• Other authors' names and the titles of books that are not yours.
• Trademarks and brand names you do not have the right to use, including series or character names owned by others.
• Misleading terms, such as a genre or subject your book does not cover.
• Claims about price, sales, or quality, such as "free", "bestseller", or "on sale".
• Program names such as Kindle Unlimited, and subjective or time-limited words such as "new".
• Content unrelated to the book, or offensive terms.

Words that already appear in your title, subtitle, or author name are commonly considered redundant, because Amazon already indexes that metadata. Using the space for different terms usually reaches more searches. Always read KDP's current keyword guidelines before you publish, since this list is a general summary, not the official text.

Simple ways to research keywords

Amazon autocomplete

Start typing a broad term into the Amazon search bar within the Books or Kindle Store department and note the suggestions. Autocomplete reflects searches people make, so it is a good source of natural phrasing. Try adding letters after your main term, such as "cozy mystery a", "cozy mystery b", to surface more variations.

Competitor listings

Open books similar to yours that sell well. Read their titles, subtitles, descriptions, and the categories they appear in. Note recurring phrases that describe your book too. Do not copy trademarked series names or author names; look for the descriptive language readers use.

Reader language

Reviews of similar books show how readers describe what they liked, such as "found family", "slow burn", or "step by step". Those phrases often make good keywords. If you are unsure how much demand a phrase reflects, the What Is Amazon BSR? guide explains how to judge the rank of the books that appear for it.

Formatting keywords with the site's tools

1. Collect every candidate phrase into one list, one per line.
2. Run it through the Keyword List Cleaner to tidy spacing and punctuation.
3. Use the Keyword Deduplicator to remove repeats, including variants that differ only in case or word order.
4. Optionally build more variations with the Keyword Combiner, then remove any that sound unnatural.
5. Paste the final list into the KDP Keyword Formatter, which packs phrases into 7 fields within the character limit and flags phrases that are too long.
6. Check each field with the Keyword Character Counter before pasting into KDP.

You can change keywords after publishing. Review them every few months, especially if you notice new phrases in autocomplete or your book's focus shifts in a revised edition.