Why are Romance Best Sellers So Long?
Comparing the average length of romance best sellers based on Kindle Unlimited status, publisher type, and subgenre.
When I posted on Threads that the average length of the July Amazon Kindle Top 100 Best Sellers in Romance was 444 pages, it generated some interesting comments, from “This is an incredibly comforting data set” to “Good god just no” (shout out to Jess K. Hardy for that one 😂).
Unfortunately, number of pages isn’t a consistent measure and Amazon doesn’t share word count for most books. However, if we use an estimate of 300 words per page, the average length of 444 pages translates to 132,600 words.
This is much longer than what is commonly cited as the average length for romance books, which a quick Google search indicates is about 70,000-100,000 words.
As another point of comparison, Harlequin is known for having rigid word count standards for romance books. Looking at their current submission guidelines, the word counts range from 50,000-75,000 words depending on the subgenre.
What is driving this longer length of romance best sellers?
Unfortunately, I can’t determine the cause from the data, but here are three potential hypotheses:
Authors in the Kindle Unlimited program write longer books because they are paid based on the number of pages reads.
Authors that are self-published write longer books because they have less pressure/influence than traditionally-published authors to edit their books down .
Authors in romance subgenres like Romantasy and Paranormal write longer books because they generally include more characters and require more worldbuilding. Also, BookTok seems to love a CHONKY romantasy!!
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To test these hypotheses, I decided to use the Amazon Kindle Store Romance Best Seller data I have so far (3 months, July to September 2025) to compare the average length of the books based on:
Kindle Unlimited Status
Publisher Type
Subgenre
Data Source
List: Amazon Kindle Store Top 100 Best Sellers in Romance (Paid), US Kindle Store. Data accessed from Kindletrends Romance Weekly Newsletter
Sales Period: July to September 2025 (3 months)
Methodology: I combined the three monthly lists (300 books), then removed duplicate books as well as any books under 100 pages (novella length). This resulted in a data set of 196 books. The average length of this group of books was 435 pages.
1. Kindle Unlimited Status
I first looked at the average length of the romance best sellers based on Kindle Unlimited (KU) status and found that the average length of books in Kindle Unlimited was actually shorter than the books that are Wide—431 pages for KU vs 448 pages for Wide.
From shortest to longest
Kindle Unlimited: 431 pages (147 books)
Wide: 448 pages (49 books)
Using an independent t-test, I determined that there is no significant difference between these two groups (𝑝>0.05).
❌ This data does not support the hypothesis that romance best sellers in Kindle Unlimited are longer.
2. Publisher Type
Next I looked at the average length of the romance best sellers based on publisher type and found that books from Big Five publishers had the shortest average length at 405 pages, while books from Other Traditional publishers had the longest average length at 471 pages. Self-published books fell in the middle with an average length of 435 pages.
From shortest to longest
Big 5: 405 pages (39 books)
Self Published: 435 pages (123 books)
Other Traditional: 471 pages (34 books)
Using a one-way ANOVA test, I determined that there is no significant difference between these three groups (𝑝>0.05).
❌ This data does not support the hypothesis that self-published romance best sellers are longer than traditionally-published romance best sellers.
3. Subgenre
Finally, I looked at the average length of the romance best sellers based on subgenre and found some fairly substantial differences. The average length of Historical and Contemporary romance books both came in under 400 pages, while the average length of Romantasy books was almost 600 pages—201 pages longer than the average for Contemporary!
From shortest to longest
Historical: 367 pages (4 books)
Contemporary: 397 pages (143 books)
Paranormal: 459 pages (16 books)
Romantasy: 598 pages (33 books)
Using a one-way ANOVA test, I determined that there is a significant difference between the four groups (𝑝≤0.05).
To determine where the group differences are, I used the Bonferroni correction as a post-hoc test (which requires 𝑝≤0.00833) and found that the only significant difference among the four groups is between the Contemporary and Romantasy subgenres (the required p-value is much lower because we’re comparing four groups).
As a result, I decided to consolidate the subgenres into two groups, Contemporary & Historical and Romantasy & Paranormal, and compare them using a independent t-test. I found that there is a significant difference between these two groups (𝑝≤0.05).
✅ This data does support the hypothesis that Romantasy and Paranormal romance best sellers are longer than Contemporary and Historical romance best sellers.
Of the three factors tested, it appears that subgenre is the only significant factor driving the longer length of romance best sellers.
What is your preference when it comes to book length? Let me know in the comments below!