.cbz File Extension
.cbz comic archive is, which apps open it, how Poly supports it, and when PDF, EPUB, or another comic format may work better. File extension details for .cbz
Full Support| File type | CBZ comic book archive |
|---|---|
| MIME type | |
| Encoding | Binary ZIP archive containing ordered page images and optional metadata |
| Operating systems | Windows, macOS, Linux |
| Opens with | calibre, MComix, Simple Comic, ZIP utilities |
| Poly support | Yes. Poly provides document features for supported CBZ comics. |
| Indexed by Poly | Yes. Poly indexes page text with OCR and page-level visual similarity. |
| Preview in Poly | Yes. CBZ files open as paginated documents in Poly's PDF viewer. |
| Poly agent | Yes. The Poly agent can read the converted comic's page text and images. |
What kind of file is a .cbz?
A .cbz file is a digital comic packaged as a ZIP archive. Its members are usually JPEG or PNG images named in reading order. Some archives also include ComicInfo.xml metadata. Comic readers use the suffix to present those images as pages instead of showing an ordinary archive directory.
IANA registers application/vnd.comicbook+zip for CBZ files. It describes CBZ as a de facto standard and lists no format-specific magic number.1 A typical non-empty ZIP starts with 50 4B 03 04, but that signature identifies only the ZIP container. Confirm that the archive holds a sensible page sequence before trusting its name.2
.cbz may let a comic reader open it. Renaming an unrelated ZIP does not convert its contents into a comic.How do I open a .cbz on my computer?
- On Windows, macOS, and Linux, calibre can read and convert comic archives. Official downloads are available for all three desktop platforms.3
- On macOS, Simple Comic supports CBZ and CBR, page spreads, and both left-to-right and right-to-left reading.4
- On Linux, MComix is another comic-focused option listed in the IANA registration.1
- With a ZIP utility, you can inspect or extract a trusted CBZ, but you lose reading controls and remembered page position.
If pages appear as 1, 10, 2, rebuild the archive with zero-padded names such as 001, 002, and 010. CBZ has no published normative specification, so readers can disagree about ordering.1
Poly support for .cbz
Poly gives supported CBZ comics a thumbnail and paginated preview. It indexes recognized page text with OCR fallback, enables page-level visual search, and lets the Poly agent read page text and images together.
The preview is a converted document view rather than a native archive browser. Keep the original when exact image bytes, ZIP properties, or native comic metadata matter. Encrypted, damaged, or unsupported archives may have limited processing.
History of .cbz
The CBZ filename convention predates its registered media type, but there is no authoritative specification that names one inventor or introduction date. It belongs to the comic-book archive family, where the final character commonly identifies the container: CBZ uses ZIP, CBR uses RAR, CBT uses TAR, and CB7 uses 7z.
IANA registered application/vnd.comicbook+zip on July 1, 2016. The registration calls CBZ and CBR de facto standards and notes that implementations may behave differently because no published CBZ specification exists.1
Working with .cbz and alternatives
| Format | Container | Practical advantage |
|---|---|---|
| CBZ | ZIP | Broad comic-reader and extraction-tool compatibility |
| CBR | RAR | Common in existing comic collections |
| CB7 | 7z | Compact archival and solid-compression options |
| Easy sharing, printing, and fixed-page viewing |
Choose CBZ for a simple image-based comic, PDF for predictable printing and broad document viewing, or EPUB when you need a documented package model, navigation, and accessibility structure. calibre can convert an ebook by using the destination extension to select the output format.5
Changing .cbr or .cb7 to .cbz does not convert its container. Extract the pages, preserve their intended order, and create a new ZIP archive. Treat unknown CBZ files as untrusted: check member paths and expanded size, and process embedded images with maintained software. IANA applies both ZIP and image-format security considerations to CBZ.1
Footnotes
- Internet Assigned Numbers Authority. application/vnd.comicbook+zip Media Type Registration. Registration date, extension, applications, interoperability notes, and security considerations. ↩ ↩2 ↩3 ↩4 ↩5
- PKWARE. .ZIP File Format Specification (APPNOTE). ZIP record signatures and container structure. ↩
- calibre. Download calibre. Official downloads are provided for Windows, macOS, and Linux. ↩
- Apple App Store. Simple Comic. The listing identifies the macOS app as a CBZ and CBR reader and describes its reading modes. ↩
- calibre. ebook-convert Command Documentation. The output format is selected from the destination filename extension. ↩