CBZ or CBR File Won't Open on iPhone? Here's How to Fix It

You tapped a comic in the Files app and nothing happened. Or iOS showed you one image and gave up. Or the file imported into a reader, displayed a cover, then refused to turn a page.

Nearly all of these have the same root cause, and once you know it the fix takes a couple of minutes. This guide explains what these files actually are, why CBR is the one that breaks on iOS specifically, then works through the fixes in order of how often they solve it. Everything here applies to both iPhone and iPad.

First, what a CBZ and a CBR actually are

This single fact explains almost every failure, so start here.

A CBZ is a ZIP archive of image files with the extension changed. Rename comic.cbz to comic.zip, unzip it, and you get a folder of JPEGs or PNGs, one per page.

A CBR is a RAR archive of image files with the extension changed. Same idea, different compression format inside.

That is the whole specification. There is no comic-specific container and no index. MobileRead's reference page states it directly: CBZ is "a ZIP compressed file containing the collection of images while Comic Book R is a RAR compressed file", and the images inside are "usually Jpeg, PNG, GIF, TIFF or more recently WebP".

The letter after CB tells you the archive format and nothing else. Z is ZIP, R is RAR, T is TAR, 7 is 7-Zip.

Why CBR is the one that breaks on iOS

ZIP is open and universally implemented. iOS has been able to expand ZIP archives directly in the Files app since iOS 13, which is why CBZ is the easy case.

RAR is proprietary. RARLAB publishes the UnRAR source, and it may be used freely to read RAR archives, but the license explicitly forbids using that code to build a RAR compressor. Three consequences follow, and they are exactly what you are hitting:

• iOS has no RAR support at all. Files will not expand a .rar and will not expand a .cbr. There is no setting to enable. Apple never shipped a RAR decoder.
• Every app that reads CBR had to add RAR decoding deliberately. That is extra work, so plenty of good readers handle CBZ, ZIP, PDF and EPUB but skip RAR. When one meets a CBR it refuses the import or shows an empty book.
• Practically no app writes CBR. Compression is the licensed half, so comic tools read CBR and export CBZ. Every conversion path below runs one direction only.

There is a sneakier version of this. RAR5, introduced with WinRAR 5.0 in 2013, uses the same extension but a redesigned internal structure, and tools built against the older RAR4 format fail on it with "unsupported format" or "invalid archive". An app can genuinely support CBR and still choke on a CBR made in the last decade. If one CBR opens and another does not, this is usually why.

Apple Books will not help with either format. It handles PDF and EPUB and rejects comic archives.

Why renaming .cbr to .cbz does not work

This is the first thing almost everyone tries, and it is a reasonable thing to try. It just does not work.

The extension is a label. It tells the operating system what to guess; it does not change a byte inside the file. Rename a CBR to CBZ and you have a RAR archive wearing a CBZ name. A reader that only implements ZIP looks for the ZIP signature at the start of the data, does not find one, and fails, often with a worse error than before because now the app expected it to work. Renaming only helps when the archive genuinely is a ZIP and the extension is what confuses something, which is Fix 4.

Fix 1: Open it in an app that reads the format natively

This solves it for most people, and it needs no conversion, no computer and no file surgery. If the file is intact, all you need is a reader that decodes RAR itself. After that the CBZ-versus-CBR distinction stops mattering to you.

1. Install a comic-capable reader and open it once so iOS registers it.
2. In the Files app, find your .cbz or .cbr.
3. Long-press the file and tap Share.
4. Scroll the row of app icons and tap your reader. If it is not there, scroll to the end and tap More.

Pushing the file through the share sheet deliberately beats tapping it, because tapping lets iOS choose the destination and iOS usually chooses wrong. The same trick solves most cases where an EPUB will not open on iPhone.

justRead is one option, relevant here for one reason: it repacks CBR archives on import, so a CBR opens like any other comic and you skip Fix 2 entirely. Details are on the comic reader page, and the comic and manga reader comparison covers what each app in the category actually supports.

If the file still fails after this, the file is the problem, not the app.

Fix 2: Convert the CBR to a CBZ on a desktop

Do this when you are committed to a reader that will not touch RAR, or when you want a uniform library. It needs a Mac or PC, because there is no first-party way to unpack RAR on iOS.

One correction first, because most advice online gets this wrong: Calibre cannot do this. Calibre accepts CBZ, CBR, CB7 and CBC as input formats, but CBZ is not on its output list at all, so the Convert books dialog cannot produce one. Calibre's own maintainer answers the question on the MobileRead forums with the manual method instead: "If you want to convert a collection of images to cbz simply zip them up and rename the zip file to have a .cbz extension." Calibre is still excellent at the rest of a reading workflow, including keeping your library synced to your phone. It is just not the CBR converter people claim.

Two routes that do work:

Kindle Comic Converter (free; Windows, macOS, Linux). Despite the name, its documented output formats are MOBI/AZW3, EPUB, KEPUB, CBZ and PDF. To read CBR input it needs the 7z executable on your system, which is the RAR-decoding half of the job.

1. Install Kindle Comic Converter, plus 7-Zip on Windows or Linux and p7zip on macOS.
2. Drag the CBR into the window.
3. Set the output format to CBZ and convert.
4. Move the result to your phone with AirDrop, iCloud Drive, or the share sheet from Fix 1.

CBconvert (free, cross-platform). A dedicated comic converter that reads CBR, CBZ, CB7, CBT, PDF and EPUB and writes ZIP archives. Use it for batch-processing a whole shelf; it can re-encode oversized images at the same time.

Fix 3: Re-zip the images yourself

The universal fallback. It works on a malformed archive, one your converter refuses, or a technically valid CBZ built so badly that readers reject it.

1. Extract the archive with a RAR-capable tool. On macOS, The Unarchiver handles RAR including version 5. On Windows and Linux, 7-Zip does the same; RAR5 extraction has been in 7-Zip since version 15.06.
2. Check the extracted folder. You want a flat folder of image files and nothing else. Delete stray Thumbs.db and .nfo files, advert pages, and empty subfolders.
3. Check that the filenames sort correctly. See Fix 5 if they do not, and fix them now rather than after zipping.
4. Select the images themselves, not the folder containing them, and compress them into a ZIP.
5. Rename the .zip to .cbz.

That is a valid comic archive. There is nothing more to it.

Fix 4: The Files app route, and where it stops

You can do a fair amount on the device, as long as the file is a CBZ.

1. In Files, long-press the file and tap Rename.
2. Change .cbz to .zip. Confirm the warning.
3. Tap the file. Files expands it into a folder of images in the same location.
4. To rebuild it, select the images, tap the three-dot menu, choose Compress, then rename the resulting Archive.zip to something ending in .cbz.

Where it stops: this does nothing for a CBR, because there is no RAR decoder anywhere in iOS to invoke. Renaming a CBR to .zip gives you a file Files cannot expand. It is also a diagnostic rather than a way to read. A folder of loose images has no reliable page order, no memory of where you stopped, and no spread handling. Use it to confirm the archive is intact, then go back to Fix 1.

Fix 5: The pages are in the wrong order

Nothing is broken here. The archive is fine, the reader is fine, and the comic still reads page one, page ten, page two.

A plain comic archive has no page-order field. Readers fall back to sorting filenames, and MobileRead's reference states the convention: the images "are displayed in alphabetical order". Alphabetical sorting compares character by character, so page10.jpg comes before page2.jpg because 1 sorts before 2. Some readers apply a smarter numeric sort; many do not, and you cannot count on it.

The fix is zero-padding, done once:

1. Extract the archive as in Fix 3.
2. Rename so every number has the same digit count: page001.jpg, page002.jpg, and so on. Three digits covers 999 pages. On macOS, select all the files, right-click, choose Rename and use Format with a number sequence. On Windows, any bulk rename tool does it.
3. Re-zip and rename to .cbz.

Watch for a cover named cover.jpg. Alphabetically it lands after page, so it can end up as the last page. Rename it 000.jpg and it returns to the front.

The other reasons a comic will not open

If nothing above matched, work down this list.

The download is corrupt or incomplete. The most common non-format cause. Check the file size in Files, shown under the filename. A full-colour issue usually runs to tens of megabytes and a manga volume often more. If your file is a few kilobytes, the download failed and you are holding an error page with a comic extension. Delete it and download again on a stable connection.

The archive is password protected. The iOS Files app does not prompt for a password and simply fails, and most comic readers do not implement encrypted archives either. Extract it on a desktop with the password, then re-zip without encryption using Fix 3.

The images are inside nested folders. An archive holding Volume 1/Chapter 1/001.jpg rather than 001.jpg at the root. Some readers walk into subfolders, some show an empty book, some order the chapters unpredictably. Flatten it with Fix 3.

The archive contains things that are not images. Release notes, .nfo files, scanner credits, an embedded advert. At best these become junk pages; at worst the reader counts them as pages and your page numbers stop matching the comic.

It is not actually a comic archive. Two common cases: a .cbz that is really a ZIP full of PDFs, one per chapter, which no comic reader will paginate correctly, so extract it and read the PDFs directly; and a plain PDF with the extension changed, which opens fine once you rename it back to .pdf.

The file is genuinely too large. A high-resolution scanned collection can run to several gigabytes in one archive, and decoding needs both storage headroom and memory. On an older device a single enormous archive can fail where the same comic split by volume works fine.

Manga that opens but reads the wrong way

If the file opens perfectly and the pages simply run backwards, nothing is wrong with the archive. Reading direction is not a property of the archive at all; a ZIP has no opinion about which way you turn a page.

Direction comes from metadata, and the convention is a file named exactly ComicInfo.xml at the root of the archive. Kavita's documentation states the placement rule: "This file must be named ComicInfo.xml and be at the root of the archive." The element controlling direction is Manga, whose allowed values in the ComicInfo v2.0 schema are Unknown, No, Yes and YesAndRightToLeft. The Anansi Project specification says of the last that it "also defines the reading direction as right-to-left when set to YesAndRightToLeft". In practice a right-to-left manga carries this:

<?xml version="1.0"?>
<ComicInfo>
  <Series>Your Series</Series>
  <Number>1</Number>
  <Manga>YesAndRightToLeft</Manga>
</ComicInfo>

Two things follow. If your file has no ComicInfo.xml, no app can know. There is no signal to read, so you set the direction yourself, and what matters is that the app remembers it per book so a right-to-left manga and a left-to-right comic can share a library. If the file does have it and the app still reads left to right, the app ignores metadata. That is common, including in well-regarded readers, and leaves you with the manual toggle. In justRead, reading direction can be set to Auto, left to right, or right to left, and manga carrying a ComicInfo.xml opens right to left with nothing set.

To add the metadata yourself, save the XML above as ComicInfo.xml, place it beside the images at the root level, and re-zip using Fix 3.

Quick diagnosis table

Frequently asked questions

Why won't my CBR open on my iPhone?

Because a CBR is a RAR archive with a different extension, and iOS has no built-in RAR support. The Files app can expand ZIP archives, which is why CBZ files are easier, but nothing in iOS unpacks RAR. You need an app that decodes RAR itself, or you convert the file on a computer.

Can I just rename a .cbr to .cbz?

No. The extension is a label on the file, not a description of its contents. Rename it and the bytes inside are still RAR, so any reader that only handles ZIP will still fail, usually with a more confusing error than before.

What is the difference between CBZ, CBR, CBT and CB7?

Only the archive format. Z is ZIP, R is RAR, T is TAR, 7 is 7-Zip. In every case the contents are ordinary image files, one per page. CBZ is the most portable because ZIP support is universal, which is why nearly every conversion tool exports CBZ.

Can I convert a CBR to a CBZ on my iPhone?

Not with anything Apple ships. iOS cannot unpack RAR, so there is no on-device starting point. The realistic answers are to convert on a computer, or to use a reader that opens CBR directly so the question stops coming up. justRead repacks CBR on import for exactly this reason.

Does Calibre convert CBR to CBZ?

No, despite what many guides claim. Calibre reads CBR and CBZ as input formats, but CBZ is not in its output list, so the Convert books dialog cannot produce one. Use Kindle Comic Converter or CBconvert, or extract and re-zip by hand.

Will Apple Books open my comics?

It opens PDFs. It does not support CBZ or CBR, and no setting changes that. If your comic is a PDF, Apple Books is fine; if it is a comic archive, you need a comic reader.

My manga reads left to right. Is the file broken?

No. Reading direction lives in metadata, not in the archive. If the file has a ComicInfo.xml at its root with <Manga>YesAndRightToLeft</Manga>, a reader that reads metadata flips automatically. If there is no such file, or the app ignores it, you set the direction yourself and the app should remember that choice per book.

Once it opens

The short version: a CBZ is a ZIP, a CBR is a RAR, iOS can open one of those and not the other, and renaming changes nothing inside. Either use a reader that decodes RAR, or convert once on a computer and keep your library as CBZ from then on.

If you would rather never think about archive formats again, that is the argument for the first fix over the second, and it leaves you with the part you actually care about: one page, a two page spread, or Auto that follows the device; pinch to zoom and double tap to zoom 3x on the spot you tapped; a grid of page thumbnails in place of a table of contents; and a page number field to jump straight to a page. The comic reader page covers that, and the reader comparison is where to start if you want to weigh your options first.