Calibre-Web vs Komga: Which Should You Self-Host?
Source: Dev.to
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 with CBZ/CBR files, offers first‑class Tachiyomi/Mihon integration, and provides superior metadata scraping for comic collections. Choose based on what you read.
Overview
Calibre‑Web
Calibre‑Web is a web frontend for Calibre ebook libraries. It reads an existing metadata.db database and provides a web interface for browsing, reading, downloading, and managing ebooks. Supported formats include EPUB, PDF, MOBI, and others. Features include send‑to‑Kindle, Kobo sync, OPDS feeds, and on‑the‑fly format conversion via Calibre.
Komga
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 support | No | First‑class extension |
| OPDS feed | Yes | Yes |
| Format conversion | Yes (via Calibre) | 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) |
| License | GPLv3 | MIT |
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 scales better for large comic collections once tuned.
Development & Ecosystem
| 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 benefits from Calibre’s large user base, while Komga enjoys more active development and a better‑documented API.
Choosing the Right Tool
-
Use Calibre‑Web if you:
- Already manage an ebook library with Calibre
- Need send‑to‑Kindle or Kobo device sync
- Require ebook format conversion (e.g., EPUB → MOBI)
- Want web‑based upload for adding books remotely
-
Use Komga if you:
- Primarily collect comics or manga (CBZ/CBR)
- Read on Android with Tachiyomi or Mihon
- Want metadata scraping from
ComicInfo.xml - Need a comprehensive API for integrations
- Desire series‑based organization and age‑based content restrictions
-
If you have both ebooks and comics:
- Run both services side‑by‑side, or
- Consider Kavita, which handles both types in a single app (though it lacks Calibre‑Web’s Kindle support and Komga’s Tachiyomi integration).
Self‑Hosting Guides
- Calibre‑Web – Docker container pointing at an existing Calibre library (
metadata.db). - Komga – Docker container pointing at comic/manga folders; configuration directory should reside on local storage.
- Kavita – Docker or binary installation; supports mixed media libraries.
Other Alternatives
- Audiobookshelf – Dedicated server for audiobooks (does not replace Calibre‑Web or Komga).
- Kavita – Single solution for EPUBs, PDFs, and comics, but with different feature set.