KDP keyword optimizer
Fill in your 7 Amazon KDP backend keyword fields. Get real-time feedback on character limits, duplicate words, title overlap, and the 249-byte limit.
7 keyword fields (50 characters each)
1
0/50
2
0/50
3
0/50
4
0/50
5
0/50
6
0/50
7
0/50
Keyword score
0/100 (Needs work)
Fields filled0/7
Unique words0
Total characters0/350
Total bytes6/249
How to use this tool
Enter your book title first so the tool can detect overlap. Then fill in your 7 keyword fields with search terms shoppers use to find books like yours. Use spaces between words, not commas. The tool checks for duplicate words across fields, title overlap, character limits per field, and the total 249-byte limit. Aim for a score of 80+ before pasting your keywords into KDP.
Frequently asked questions
- How many keywords can I enter for a KDP book?
- Amazon KDP gives you exactly 7 keyword fields. Each field allows up to 50 characters, giving you a total of 350 characters of backend metadata. These keywords are hidden from shoppers but directly influence how your book appears in Amazon search results.
- Should I use commas to separate keywords in a KDP field?
- No. Amazon treats spaces as natural separators, so commas are unnecessary and waste character space. Use spaces between words within each field. For example, write "stress relief adult coloring" not "stress relief, adult, coloring".
- Should I repeat words that are already in my book title?
- No. Amazon indexes your title separately from your backend keywords. Repeating title words in your keyword fields wastes valuable space. Use the keyword fields for terms that are NOT in your title to maximize your search visibility.
- What is the 249 byte limit for KDP keywords?
- Amazon limits total backend keywords to 249 bytes in US, UK, and EU marketplaces. Standard English characters use 1 byte each. If you exceed this limit by even a single byte, Amazon de-indexes your entire keyword field, making your book invisible in keyword searches.
- Can I use the same word in multiple keyword fields?
- You can, but it provides zero benefit. Amazon combines all 7 fields into a single search index. A word only needs to appear once across all fields to be indexed. Repeating words wastes space you could use for additional search terms.
- What keywords work best for coloring books on KDP?
- Effective coloring book keywords include your niche (animals, mandala, floral), your audience (adults, seniors, kids ages 4-8), descriptive features (bold and easy, large print, stress relief), and related search terms (activity book, gift for mom, relaxation). Avoid generic terms like "book" or "coloring" if they are already in your title.
Last updated: March 2026. Based on Amazon KDP's current keyword field requirements for the US marketplace.