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🚀 Product Hunt Launch Special

First 10 Authors Get FREE Author Pro Tier ($49 Beta Value)

We're building case studies for our Product Hunt launch. Apply now for FREE manuscript testing. 6 spots remaining.

Claim Your Free Spot →

Offer ends January 31, 2026 or when all spots are filled

What Is Delta Reader?

Traditional beta readers give you opinions.
We give you behavioral data.

Research-Backed
Built on Narrative Transportation, Flow State, Geneva Emotion Wheel & Mind-Wandering studies
AI-Free
Pure heuristics turn reader behavior into measurable insights
Behavioral Data
Track what readers DO, not what they SAY

Send readers a link. They read in our web-based e-reader on any device and react in real time. We capture where behaviors change.

Traditional Beta Feedback

  • chat_bubble"The middle dragged a bit"
  • chat_bubble"I got confused at the end"
  • chat_bubble"Chapter 7 didn't work for me"
  • chat_bubble"Some readers loved it, some didn't"

Vague opinions. No exact locations. Hours of guesswork.

Delta Reader

  • analytics"Chapters 11-14: 12% faster speed + frustrated"
  • analytics"Ch 7: 8 readers in a flow state"
  • analytics"3 readers dropped at 58% through Ch 9 | Last emotions (Ch 8): frustrated, protagonist"
  • analytics"8 readers highlighted same quote in Ch 15"

Exact locations. Behavioral data. Zero guesswork.

Who Uses Delta Reader

edit

Authors

Testing manuscripts before publication. Get precision feedback on exactly what to revise.

business

Publishers

Evaluating acquisitions with behavioral data. See exactly where manuscripts succeed or fail.

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Editors

Diagnosing manuscript issues with reader data. Skip speculation, focus on patterns.

Contact us for more detials!

Experience the Delta Reader

See what Delta Reader can do for your manuscript
Actual Output From Your Reports

See What You'll Get

Real examples from actual Delta Reader reports. No mockups—this is what authors receive.

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Executive Snapshot

Executive Snapshot showing completion rate, higher and lower frequency behaviors

High-level overview showing completion rates, higher frequency behaviors (curious/invested responses), and lower frequency behaviors (discontinuations, confused reactions).

Click to enlarge

Author Pro

Emotion Distribution Over Time

Emotion Distribution chart showing curious/invested, following/uncertain, and bored/frustrated trends across chapters

Line chart showing how reader emotional responses evolved chapter by chapter. Track engagement peaks, neutral zones, and disengagement patterns throughout your manuscript.

Beta Special: Full Author Pro tier just $49 during beta testing

Click to enlarge

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Momentum Direction

Momentum Direction showing engagement consistency and chapters requiring attention

Shows whether reader engagement builds, stays steady, or fades throughout your manuscript. Includes "Chapters Requiring Attention" with specific emotions readers felt in problem areas.

Click to enlarge

Understanding the Core Metrics

Reading Speed

What it is: How fast readers moved through each chapter compared to their personal baseline (100% = their normal pace).

Example: "Chapter 8: 138% speed" means readers moved 38% faster than normal—either racing through action or skimming boring parts.

Dropout Rate

What it is: Percentage of readers who stopped reading this chapter and never came back.

Example: "Ch 8: 13% dropout" means 2 out of 16 readers quit during this chapter. Multiple dropouts in one spot = fix it.

Emotional Reactions

What it is: Times readers clicked emotion buttons while reading. Not how they felt about the story—how they felt while reading.

Example: "frustrated (8), anxious (6)" in Ch 8 = readers struggled with that chapter, not that the plot made them anxious.

Ready to give your manuscript an X-ray?

See exactly where behaviors shift throughout your manuscript.

Request Demo

Simple Pricing

Honest pricing. Powerful insights.

rocket_launch Indie Starter

$47
per manuscript
  • Up to 10 beta readers
  • Core diagnostics
  • Downloadable HTML report
  • Dropout & speed tracking
  • 30-day campaign window
Get Started
Beta Special

workspace_premium Author Pro

$49 $97
per manuscript • 50% off during beta
  • 20–25 beta readers
  • Full precision diagnostics
  • Reader State Heatmaps
  • Publisher-style report view
  • Highlight validation tracking
  • Reading speed analytics (WPM)
  • Pattern detection drill-downs
  • Shareable analytics links
  • 60-day campaign window
Get Started

corporate_fare Publisher / Studio

$497/mo
or $4,970/year Save $994!
  • Everything in Author Pro, plus:
  • 10 active campaigns (run multiple manuscripts)
  • Campaign comparison analytics
  • White-label reports
  • Priority support
Contact Us

Manuscript Behavioral Diagnostics

Beta reader analytics for authors and publishers seeking precision editorial feedback

Request Demo