Sudowrite vs NovelAI vs WriteAIBook: Which is Best for KDP?
I published 350 AI-generated novels on Amazon KDP in 6 months and made €18,000 - here's what I learned about choosing the right AI writing tool.
What's Inside
The Problem: Why Most AI-Generated KDP Books Fail
When I started, I made every mistake in the book (literally):
- Wasting hours editing incoherent outputs from general AI tools
- Picking dead-end genres (my sci-fi books made €12 each vs. €156 for dark romance)
- Assuming "more words = more money" (80% of my KU page reads came from books under 30k words)
Key Issue
General AI writing tools aren't built for KDP's quirks. They're great for brainstorming or short stories, but they fail at series consistency, genre-specific tropes, and fast bulk output needed for KDP success.
Step-by-Step: How to Pick the Best AI Tool for KDP
1. Test Output Quality with Your Target Genre
I generated 20 chapters each from Sudowrite, NovelAI, and WriteAIBook in dark romance—my top-earning genre. Here's what I found:
| Tool | Time per Chapter | Trope Accuracy | Editing Needed |
|---|---|---|---|
| Sudowrite | 8 minutes | 40% | 45 minutes |
| NovelAI | 12 minutes | 30% | 60 minutes |
| WriteAIBook | 3 minutes | 85% | 15 minutes |
Key Insight: WriteAIBook's genre-specific training cut my editing time by 70%.
2. Calculate Cost per Book
General AI tools charge per word. KDP requires volume. Here's the math for a 30k-word novel:
- Sudowrite: $0.10/1k words → $3/book
- NovelAI: $15/month for 6k words → $7.50/book (and you're throttled)
- WriteAIBook: €8 for 250 credits → €1.28/book (200 credits = 30k words)
At 50 books/month, that's €64 vs. $375.
My Data: Real Results from 350 Books
Performance Highlights
- Best performer: Bought by the Dragon King (Dark Romance) – €892 in 4 months
- Worst performer: Space Pirates of Alpha Centauri (Sci-Fi) – €12 lifetime
- Avg. revenue per book: €51 (but €156 for dark romance vs. €12 for sci-fi)
Surprising finding: Books in a 5-book series earned 4x more than standalones (KU read-through). WriteAIBook's series continuity features doubled my completion rates.
3 Deadly Mistakes to Avoid
1. Ignoring Genre Economics
My dark romance books earned 13x more than sci-fi. Yet 90% of AI tutorials push "write what you love." Bad advice. Use tools that optimize for profitable genres.
2. Over-Editing
Spending 5 hours perfecting one book? Stop. I made €2,400/month by:
- Generating 2 books/day
- Editing just 30 minutes per book (find/replace repetitive phrases)
- Publishing 50+ books before optimizing
3. Using General-Purpose AI
Tools like ChatGPT require endless prompting. WriteAIBook's pre-set genre templates let me generate a publishable draft in 60 minutes vs. 6 hours.
Final Verdict: Sudowrite vs NovelAI vs WriteAIBook
| Feature | Sudowrite | NovelAI | WriteAIBook |
|---|---|---|---|
| KDP-optimized | ❌ | ❌ | ✅ |
| Cost per book | $3+ | $7.50+ | €1.28 |
| Editing time | 45 min | 60 min | 15 min |
| Series support | Manual | Manual | Auto |
For KDP publishers: WriteAIBook is the only tool built specifically for high-volume, profitable publishing.
Try WriteAIBook Free (30 Credits)Generate your first 3 chapters in under 10 minutes.
P.S. My #1 piece of advice? Publish 20 books before tweaking anything. Consistency beats perfection in KDP. (My first 10 books made €84 total. Books 11-350 made €17,916.)
Next: improve your KDP workflow
If your bottleneck is consistency, packaging, or shipping speed, start here:
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