send2kindle

A CLI tool that extracts web articles, converts them to EPUB, and sends them to your Kindle device via email.

Features

• Extract articles from any URL using Mozilla's Readability
• Extract tweets and Twitter/X articles via the fxtwitter API
• Convert to EPUB format via pandoc
• Book mode — combine multiple URLs into a single EPUB with chapters
• Send PDFs directly to Kindle (with optional text extraction via --extract)
• Debug mode to preview EPUBs locally before sending

Prerequisites

• Node.js 18+ (uses built-in fetch)
• pandoc — for HTML-to-EPUB conversion

Install pandoc with your package manager:

# Ubuntu/Debian
sudo apt install pandoc

# macOS
brew install pandoc

# Fedora
sudo dnf install pandoc

Installation

# Install globally from npm
npm install -g @kelvinlouis/send2kindle

# Or run directly with npx
npx @kelvinlouis/send2kindle https://example.com/article

Configuration

Set the following environment variables (e.g. in your .bashrc or .zshrc):

Required

| Variable | Description | | --------------- | ------------------------------------------------------ | | KINDLE_EMAIL | Your Kindle email address (e.g. [email protected]) | | SMTP_USER | Your email address for sending | | SMTP_PASSWORD | Your email password or app password |

Optional

| Variable | Default | Description | | ------------- | -------------------- | -------------------- | | SMTP_SERVER | smtp.gmail.com | SMTP server hostname | | SMTP_PORT | 587 | SMTP server port | | FROM_EMAIL | Value of SMTP_USER | Sender email address |

Example setup

export KINDLE_EMAIL="[email protected]"
export SMTP_USER="[email protected]"
export SMTP_PASSWORD="abcd-efgh-ijkl-mnop"  # Gmail app password

Usage

# Send a web article to Kindle
send2kindle https://example.com/some-article

# Send a PDF to Kindle (sent as-is, preserving original layout)
send2kindle /path/to/document.pdf

# Extract PDF to EPUB (loses original layout, useful for simpler/smaller PDFs)
send2kindle --extract /path/to/document.pdf
send2kindle -e /path/to/document.pdf

# Send a tweet or Twitter/X article
send2kindle https://x.com/username/status/123456789

# Debug mode: create EPUB locally without sending
send2kindle --debug https://example.com/some-article
send2kindle -d https://example.com/some-article

# Book mode: combine multiple articles into one EPUB with chapters
send2kindle --book "My Book Title" https://example.com/ch1 https://example.com/ch2
send2kindle -b "My Book Title" -a "Author Name" url1 url2 url3

Book mode

Use --book "Title" (or -b "Title") to combine multiple URLs into a single EPUB where each URL becomes a separate chapter. The article title from each URL is used as the chapter heading.

Optionally specify --author "Name" (or -a "Name") to set the book author. If omitted, the byline from the first article is used.

send2kindle --book "Gradually, Then Suddenly" --author "Parker Lewis" \
  https://nakamotoinstitute.org/library/gradually-then-suddenly/bitcoin-obsoletes-all-other-money/ \
  https://nakamotoinstitute.org/library/gradually-then-suddenly/bitcoin-not-blockchain/ \
  https://nakamotoinstitute.org/library/gradually-then-suddenly/bitcoin-is-not-backed-by-nothing/

Debug mode

Use --debug (or -d) to save the EPUB to your current directory instead of emailing it. This is useful for previewing the output before sending. No email credentials or KINDLE_EMAIL are required in debug mode.

Kindle email delivery

Amazon Kindle devices can receive documents via email. To set this up:

1. Find your Kindle email — Go to Amazon device settings and look under "Personal Document Settings" for your Send-to-Kindle email address.

2. Add your sender email to the approved list — In the same settings page, under "Approved Personal Document E-mail List", add the email address you'll be sending from (your SMTP_USER / FROM_EMAIL).

Gmail setup

If using Gmail as your SMTP provider:

1. Enable 2-Factor Authentication on your Google account
2. Create an App Password at https://myaccount.google.com/apppasswords
3. Use the App Password as your SMTP_PASSWORD

Development

git clone https://github.com/kelvin-prpl/send2kindle.git
cd send2kindle
npm install
npm link  # exposes `send2kindle` as a global command pointing to your local checkout

For AI agents

See AGENTS.md for project conventions, commands, and architecture details.

License

MIT