methods-and-tools

Purpose

This document covers methods for extracting text from Amazon Kindle ebooks, including DRM removal techniques, format conversion, and legal considerations as of 2025.

Key Changes in 2025

Amazon’s May 2025 Infrastructure Update

Amazon rolled out a critical update that significantly impacted text extraction workflows:

Blocked older Kindle for PC versions (1.17 and 1.24) that were primary gateways for downloadable, easily decryptable files
Forced “Hardened KFX” encryption on all new downloads through modern clients (Kindle for PC 2.8.0+)
Removed download capability in February 26, 2025 update, making it harder to get ebooks into Calibre without a physical Kindle
Books downloaded in 2025 use stronger encryption that breaks many legacy DeDRM workflows

Impact: Long-standing plug-and-play methods became unreliable or ineffective after May 2025.

Methods for Text Extraction

1. Calibre + DeDRM Plugin (Best Free Option)

Status: Still functional but more complex as of 2025

Requirements:

Calibre (free ebook manager and converter)
DeDRM plugin v10.0.14 (latest working version with KFX Key Extractor)
Kindle for PC 2.8.0 (forced by Amazon) or older versions if available
KFX_Input plugin (required for KFX format books)

Setup Process:

Download DeDRM_tools.zip from GitHub
Extract and locate DeDRM_plugin.zip (NOT the tools.zip)
Install in Calibre: Preferences → Plugins → Load plugin from file
Install KFX_Input plugin for KFX format support
Extract Kindle keys using KindleKeyExtractor28.exe
- Copy to: C:\Users\username\AppData\Local\Amazon\Kindle\application
Add books to Calibre library for automatic DRM removal

Key GitHub Resources:

Fork (maintained): https://github.com/noDRM/DeDRM_tools
Original (unmaintained): https://github.com/apprenticeharper/DeDRM_tools

Limitations:

Books from 2025: Hardened KFX encryption may fail even with correct setup
Complex workflow: No longer plug-and-play; requires manual key extraction
Version dependencies: Must use specific Kindle for PC versions

2. Physical Kindle Device Method

Why it works: Physical Kindle devices store books in formats that can be transferred and decrypted.

Process:

Download books to physical Kindle e-reader (12th gen or later)
Connect Kindle to computer via USB
Locate books in Internal Storage\documents\
Important: Copy entire book folder including .sdr folder (required for DRM removal)
Use Calibre + DeDRM plugin to process copied files

Advantages:

More reliable than PC/Mac app downloads in 2025
Works with newer books that break PC app workflows

Disadvantages:

Requires owning a physical Kindle device
Manual file transfer process

3. AI-Based Extraction (kindle-ai-export)

Tool: kindle-ai-export

How it works:

Logs into Kindle web reader using Playwright automation
Exports each page as PNG image
Uses multimodal LLM (default: GPT-4.1-mini) to transcribe text from images
Converts raw text to PDF, EPUB, or other formats
Can generate AI-narrated audiobooks

Advantages:

Bypasses traditional DRM entirely (works via web reader)
Works with any Kindle book accessible via web reader
Flexible output formats
Completely automated after setup

Disadvantages:

Transcription errors: OCR via LLM is not 100% deterministic
API costs: Requires OpenAI API or compatible vLLM provider
Slower: Image-to-text conversion takes time
Quality variance: Complex formatting may not translate perfectly

Best for: Books where some transcription errors are acceptable, or when traditional methods fail.

4. Commercial Tools

Epubor Ultimate ($29.99)

Dedicated DRM removal + format conversion tool
Supports Kindle, Nook, Kobo formats
More user-friendly than Calibre setup
Paid solution but actively maintained

Epubor Kindle Converter

Specifically handles 2025 Kindle books
Only option for Mac users with new Kindle books
Supports latest Kindle encryption schemes

BookFab Kindle Converter

Native DRM removal for 2025 Kindle files
Designed to handle Hardened KFX encryption

Trade-offs: Paid tools offer simpler workflows and better support for 2025 books, but come with licensing costs.

5. Copying Text via Highlights (Limited)

How it works:

Highlight text in Kindle apps/devices
Highlights sync to Amazon Notebook
Copy text from web-based Notebook

Limitations:

10% copy limit on most books (Kindle for PC/Mac)
Manual, tedious process for large amounts of text
Not suitable for full book extraction
Error message: “Your copy limit for this book has been exceeded”

Best for: Extracting specific quotes or short passages only.

Format Conversion

Understanding Kindle Formats

AZW: Original Kindle format (based on MOBI with DRM)
AZW3 (KF8): Enhanced format with better formatting support
KFX: Latest format with Hardened encryption (2025)
MOBI: Older open format (Amazon stopped using)

Conversion Tools

Calibre (Free)

Add AZW/AZW3 file to Calibre library
Select book → “Convert books”
Choose output format (EPUB, PDF, TXT, etc.)
Requires DRM removal first via DeDRM plugin

Online Converters (Limited Use)

CloudConvert, Zamzar, online-convert.com
Cannot remove DRM - only work with DRM-free files
Useful for public domain books from Project Gutenberg

Alternative: Just Use Kindle Apps

Amazon announced in 2022 that newer Kindle devices support EPUB natively. For cross-platform reading:

Use Kindle for iPad/Android/Mac/PC apps
No conversion needed if staying within Amazon ecosystem

Legal Considerations

United States

DMCA Act: Prohibits circumvention of DRM technology
Copyright law: Illegal to copy or distribute copyrighted material without permission
Personal use: Converting for personal backup is generally tolerated but technically violates DMCA
Distribution: Sharing DRM-removed files is clearly illegal

General Principles

DRM removal isn’t inherently illegal, but distribution of copyrighted content is
Public domain books: Freely convertible (e.g., Project Gutenberg)
Local laws vary: Verify regulations in your jurisdiction
Personal backups: Most reasonable use, but check local laws

This guide is intended for educational and personal backup purposes only.

Recommendations by Use Case

Use Case	Recommended Method	Why
Personal backup (2024 or earlier books)	Calibre + DeDRM plugin	Free, reliable for older books
Personal backup (2025 books)	Physical Kindle device method	More reliable with new encryption
Quick extraction, cost not an issue	Commercial tool (Epubor/BookFab)	Simpler workflow, better support
When other methods fail	kindle-ai-export	Bypasses DRM via web reader
Just need quotes	Highlights method	Legal, no DRM issues
Public domain books	Any method	No DRM to worry about

Key Takeaways

2025 changed everything: Amazon’s encryption updates broke many legacy workflows
Physical Kindle is more reliable: For new books, physical device method works better than PC apps
AI extraction is the wildcard: Works when traditional methods fail, but with trade-offs
Legal gray area: DRM removal for personal use is technically illegal under DMCA but rarely enforced
Commercial tools justify cost: If time matters, paid tools handle 2025 books better