Komga vs Calibre-Web: Which Should You Self-Host?

Quick Verdict

Komga is better for comics and manga. Calibre-Web is better for ebooks. Komga has a purpose-built comic reader with page-by-page navigation, series tracking, and OPDS PSE (page streaming) support. Calibre-Web excels at ebook management — format conversion, Kindle integration, and a broader metadata ecosystem. Pick based on your primary content type.

Overview

Komga is a media server for comics, manga, and books in CBZ, CBR, PDF, and EPUB formats. Built in Kotlin with a modern Vue.js frontend, it provides a polished web reader optimized for image-based content, series/collection management, read progress tracking, and a REST API. It also functions as an OPDS server for mobile reading apps.

Calibre-Web is a web interface for Calibre ebook libraries. It handles EPUB, PDF, MOBI, CBZ/CBR, and more. It provides in-browser reading, metadata management, format conversion (via Calibre binaries), OPDS catalogs, and Kindle email delivery. It wraps a Calibre database, making it compatible with the Calibre desktop ecosystem.

Feature Comparison

FeatureKomgaCalibre-Web
Primary contentComics, manga, booksEbooks (all formats)
CBZ/CBR readingExcellent (purpose-built)Basic
EPUB readingYesYes (better reader)
PDF readingYesYes
Page-by-page navigationYes (optimized for comics)Basic
Double-page spreadYesNo
Reading direction (RTL for manga)YesNo
Series managementYes (automatic detection)Limited
Read progress trackingYes (per-page)Yes (per-book)
CollectionsYesYes (bookshelves)
Metadata editingYesYes (richer sources)
Format conversionNoYes (via Calibre)
Send to KindleNoYes
OPDS catalogYes (OPDS + OPDS PSE)Yes (OPDS)
Multi-userYesYes
REST APIYes (comprehensive)Limited
Upload via web UIYes (drag-and-drop)Yes
External databaseNo (embedded H2/SQLite)Calibre SQLite database
Docker containers11
RAM usage200-400 MB (JVM)50-100 MB
LicenseMITGPL-3.0

Installation Complexity

Komga is simple — one container, point it at your comics/books directory. No external database, no prerequisites. The web UI handles library setup on first access. Being a JVM application, it does use more RAM than Python-based alternatives.

Calibre-Web requires an existing Calibre database. If you’re coming from Calibre desktop, point it at your existing library. If starting fresh, you need to create an empty Calibre library first. The LinuxServer.io Docker image simplifies this but it’s still an extra step compared to Komga’s zero-dependency approach.

Performance and Resource Usage

MetricKomgaCalibre-Web
RAM (idle)200-400 MB50-100 MB
RAM (active reading)300-500 MB80-150 MB
CPU (library scan)Moderate (thumbnail generation)Low
Disk (application)~100 MB~50 MB
Startup time5-10 seconds (JVM)2-3 seconds

Komga’s JVM runtime means higher baseline RAM usage. On a 1 GB RAM server, this is significant. On anything with 2+ GB, it’s a non-issue. Komga’s thumbnail generation is CPU-intensive during initial library scans but only runs once per new file.

Calibre-Web is lighter, but if you enable format conversion, the Calibre binary processes can temporarily spike CPU and RAM.

Community and Support

Komga has a focused, active community (~4K GitHub stars). The developer is responsive, and releases are frequent. Documentation is thorough and well-maintained. The Tachiyomi/Mihon manga reader community has adopted Komga as a primary backend.

Calibre-Web has a larger user base (~13K GitHub stars) due to its connection to the massive Calibre ecosystem. Development is steady. The project benefits from years of stability and a mature feature set.

Use Cases

Choose Komga If…

  • Your primary content is comics, manga, or graphic novels
  • You want a polished page-by-page reading experience in the browser
  • You need right-to-left reading support for manga
  • You use Tachiyomi/Mihon on Android and want a self-hosted backend
  • You want series tracking with automatic organization
  • You don’t need format conversion or Kindle integration

Choose Calibre-Web If…

  • Your primary content is text-based ebooks (EPUB, MOBI)
  • You need format conversion (EPUB → MOBI, etc.)
  • You want to send books directly to Kindle
  • You already use Calibre desktop
  • You want richer metadata from Google Books, Amazon, and other sources
  • Memory is constrained (50 MB vs 300 MB baseline)

Final Verdict

Choose based on content type. For comics and manga, Komga provides a significantly better reading experience with features Calibre-Web can’t match — double-page spreads, RTL reading, page-level progress tracking, and Tachiyomi integration. For ebooks, Calibre-Web’s format conversion, Kindle delivery, and deeper metadata integration make it the better choice.

If you have both comics and ebooks, run both. They can coexist on the same server without conflict. Or consider Kavita, which attempts to handle both content types in a single application.

FAQ

Can Komga handle regular ebooks (EPUB)?

Yes, Komga reads EPUB files. However, its reader is optimized for image-based content. For text-heavy EPUBs, Calibre-Web provides a better reading experience with adjustable fonts, themes, and text reflow.

Does Calibre-Web work without Calibre desktop?

You need a Calibre database file, but you don’t need Calibre desktop running. Create the initial library once, then manage everything through the web interface.

Which is better for PDFs?

Both handle PDFs, but neither is optimized for them. For comics in PDF format, Komga is better (page navigation). For text PDFs, Calibre-Web is marginally better. For a dedicated PDF tool, consider Stirling-PDF.

Can I migrate from Calibre-Web to Komga?

Not directly — they use different database formats. However, you can point Komga at the same book files. You’ll lose Calibre-specific metadata (custom columns, tags) but keep the files themselves.