diff --git a/calibre_web/CHANGELOG.md b/calibre_web/CHANGELOG.md
index a96ee742e..d26368446 100644
--- a/calibre_web/CHANGELOG.md
+++ b/calibre_web/CHANGELOG.md
@@ -1,4 +1,7 @@
 
+## 0.6.26-2 (2026-04-06)
+- Fix: Install calibre (calibredb) at build time to fix 500 error when downloading books
+
 ## 0.6.26 (2026-02-07)
 - Update to latest version from linuxserver/docker-calibre-web (changelog : https://github.com/linuxserver/docker-calibre-web/releases)
 - Added support for configuring extra environment variables via the `env_vars` add-on option alongside config.yaml. See https://github.com/alexbelgium/hassio-addons/wiki/Add-Environment-variables-to-your-Addon-2 for details.
diff --git a/calibre_web/Dockerfile b/calibre_web/Dockerfile
index b87ebb8b0..9b564feed 100644
--- a/calibre_web/Dockerfile
+++ b/calibre_web/Dockerfile
@@ -35,6 +35,12 @@ RUN \
     && echo '#!/bin/sh' > /usr/bin/xdg-desktop-menu && chmod +x /usr/bin/xdg-desktop-menu \
     && echo '#!/bin/sh' > /usr/bin/xdg-mime && chmod +x /usr/bin/xdg-mime
 
+# Install calibre binaries (provides calibredb required for book downloads)
+# hadolint ignore=DL4006
+RUN \
+    wget -nv -O- https://download.calibre-ebook.com/linux-installer.sh | sh /dev/stdin install_dir=/opt/calibre
+ENV PATH="/opt/calibre:${PATH}"
+
 # Global LSIO modifications
 COPY ha_lsio.sh /ha_lsio.sh
 ARG CONFIGLOCATION="/config"
diff --git a/calibre_web/config.yaml b/calibre_web/config.yaml
index ab0e2af0b..b63722503 100644
--- a/calibre_web/config.yaml
+++ b/calibre_web/config.yaml
@@ -116,5 +116,5 @@ schema:
 slug: calibre-web
 udev: true
 url: https://github.com/alexbelgium/hassio-addons/tree/master/calibre_web
-version: "0.6.26"
+version: "0.6.26-2"
 video: true