Quick Verdict
These serve different primary audiences. Calibre-Web is for ebook libraries — it manages EPUBs, supports send-to-Kindle, syncs with Kobo devices, and integrates with Calibre's metadata system. Komga is for comics and manga — it excels at CBZ/CBR files, has first-class Tachiyomi/Mihon integration, and offers superior metadata scraping for comic collections. Pick based on what you read.
Overview
Calibre-Web is a web frontend for Calibre ebook libraries. It reads an existing Calibre metadata.db database and provides a web interface for browsing, reading, downloading, and managing ebooks. It supports EPUB, PDF, MOBI, and other ebook formats with send-to-Kindle, Kobo sync, OPDS, and format conversion capabilities.
Komga is a comics and manga media server that scans directories of CBZ, CBR, EPUB, and PDF files, organizes them into series, and serves them through a web reader and API. It focuses on comic-specific metadata (ComicInfo.xml), series organization, and integration with manga reader apps like Tachiyomi/Mihon.
Feature Comparison
| Feature | Calibre-Web | Komga |
|---|---|---|
| Primary format | EPUB, PDF, MOBI | CBZ, CBR, EPUB, PDF |
| Ebook reading | Good web reader | Basic (optimized for comics) |
| Comic/manga reading | Limited | Excellent |
| Calibre integration | Native (reads metadata.db) | None |
| Send-to-Kindle | Yes | No |
| Kobo sync | Yes | No |
| Tachiyomi/Mihon | No | First-class extension |
| OPDS feed | Yes | Yes |
| Format conversion | Yes (with calibre mod) | No |
| Metadata management | Via Calibre | ComicInfo.xml + API |
| Series organization | Via Calibre metadata | Folder-based auto-detection |
| User management | Multi-user with permissions | Multi-user with library restrictions |
| API | Limited | Comprehensive REST API |
| Upload via web | Yes | No |
| Content restrictions | Per-user access | Age-based per user |
| Runtime | Python/Flask | Kotlin/Spring (JVM) |
| RAM (idle) | ~100 MB | ~200 MB |
| License | GPLv3 | MIT |
Installation Complexity
Calibre-Web: Requires an existing Calibre library with metadata.db. If you don't have one, you need to create it first. Docker setup is one container.
Komga: No prerequisites. Point it at your file directories and start. Docker setup is one container, but the config directory must be on local storage.
Winner: Komga for pure simplicity. Calibre-Web's Calibre dependency adds a setup step.
Performance and Resource Usage
| Metric | Calibre-Web | Komga |
|---|---|---|
| Idle RAM | ~100 MB | ~200 MB |
| Active use RAM | ~200 MB | 500 MB+ |
| Library size limit | ~20,000 books | 50,000+ files (with heap tuning) |
| Scan speed | Instant (reads existing DB) | Moderate (generates thumbnails) |
| Disk for cache | Minimal | 500 MB - 2 GB |
Calibre-Web is lighter because it reads an existing database rather than building its own. Komga's JVM baseline uses more memory but handles larger libraries once configured.
Community and Support
| Aspect | Calibre-Web | Komga |
|---|---|---|
| GitHub stars | 13,000+ | 4,500+ |
| Development pace | Slow (last major release 2021) | Active (regular releases) |
| Documentation | Community guides | Official docs (komga.org) |
| Ecosystem | Calibre + OPDS readers | Tachiyomi/Mihon + API consumers |
Calibre-Web has more stars due to Calibre's large user base, but Komga has more active development and a better-documented API.
Use Cases
Choose Calibre-Web If...
- You already use Calibre to manage your ebook library
- You want send-to-Kindle functionality
- You own a Kobo and want direct device sync
- You need ebook format conversion (EPUB → MOBI, etc.)
- Your collection is primarily EPUBs and PDFs
- You want web-based upload for adding books remotely
Choose Komga If...
- Your collection is primarily comics and manga (CBZ/CBR files)
- You read on Android with Tachiyomi/Mihon
- You want metadata scraping from ComicInfo.xml
- You need a comprehensive API for integrations
- You want server-wide collections and reading lists
- You don't use Calibre and don't want to start
Final Verdict
Use the tool that matches your content type. Calibre-Web is the right answer for ebook readers — the Calibre integration, send-to-Kindle, and Kobo sync are features that comic server apps simply don't offer. Komga is the right answer for comic and manga readers — the series organization, Tachiyomi integration, and comic reader are purpose-built for that content.
If you have both ebooks and comics, consider running both. Or use Kavita, which handles both ebooks and comics reasonably well in a single app.
FAQ
Can I run Calibre-Web and Komga together?
Yes. Point Calibre-Web at your Calibre ebook library and Komga at your comics/manga folders. They serve different content and don't conflict.
Which should I choose if I have both ebooks and comics?
Run both, or use Kavita as a single solution. Kavita handles EPUB and comics in one app, though it lacks Calibre-Web's send-to-Kindle and Komga's Tachiyomi integration.
Does either support audiobooks?
No. For audiobooks, use Audiobookshelf.
Can Komga read Calibre libraries?
No. Komga manages its own library based on folder structure. It doesn't read Calibre's metadata.db.
Top comments (0)