Convert CBR to EPUB

CBR files are RAR archives of page images — a format most converters and e-readers refuse to touch. Tanko extracts the RAR right in your browser (old RAR4 and modern RAR5 alike), optimizes every page for your device, and packages a fixed-layout EPUB that Kindle, Kobo, and every reading app understands.

Device
Reading direction
Two-page spreads

Nothing is uploaded — the RAR engine runs client-side, so there's no size limit, no queue, and your files stay on your machine.

How to convert CBR to EPUB without WinRAR

  1. Drop the .cbr on the converter. The RAR decoder is the unrar library compiled to WebAssembly and runs inside the browser tab, so nothing needs installing and nothing is uploaded. RAR4 and RAR5 archives both work.
  2. Wait for the extraction pass. Most CBRs are solid archives, meaning every file depends on the ones before it. Tanko extracts the whole archive once on the first page read and serves the rest from memory, so a large file shows a pause before page one and then moves quickly.
  3. Pick your device, direction, and spread mode. These work the same as for a CBZ; the archive type has no influence on how pages are processed once they are out of the container.
  4. Download the EPUB. The output is the same fixed-layout EPUB tanko builds from any input, named after the CBR, with pages sized for the profile you chose.

Why CBR is harder to convert than CBZ

CBR is a RAR archive, and RAR is a proprietary format: the decompressor is freely licensed but the compressor is not, so it never became a standard library on every platform the way zip did. E-readers ship without a RAR decoder, and many web converters quietly skip CBR for the same reason.

Tanko sidesteps this by bundling unrar as WebAssembly and running it in a Web Worker next to the image pipeline. The archive is read from a byte buffer in memory, the file list comes from the RAR headers, and extraction happens once for the whole archive because solid RARs cannot be read out of order.

That single extraction is why a large CBR takes noticeably longer to start than a CBZ of the same size, while per-page processing afterward is identical. Memory use peaks during that step, since the unpacked images are held until they have been processed.

Mislabeled, damaged, and unsupported RAR files

The converter checks the first bytes of the file, not the extension, so a .cbr that is really a zip opens as a zip and a .cbz that is really a RAR opens as a RAR. The file still needs one of the accepted extensions (.cbz, .cbr, .zip, .rar, .pdf) to get past the file picker.

A truncated or corrupt archive fails with an error instead of producing a book with missing pages: if an entry cannot be extracted, the conversion stops. Password-protected archives are not supported, and neither are multi-volume sets split into .part1.rar, .part2.rar and so on — repack those as a single archive first.

Inside the archive the page rules are the ones any CBZ follows: JPEG, PNG, WebP, and GIF files in natural path order, with metadata files, dotfiles, and macOS resource folders ignored.

Read the guide

Frequently asked questions

My file says .cbr but won't open in other tools — will it work here?
Probably. Many "CBR" files are actually mislabeled ZIP archives (and vice versa). Tanko detects the real format from the file's bytes, not its extension, so mislabeled archives convert fine.
Do I need WinRAR or any software installed?
No — the RAR extraction engine runs inside your browser. Drop the file, download the EPUB.
Is CBR better quality than CBZ?
No. Both contain the same page images; the only difference is the container, RAR versus zip. RAR compresses already-compressed JPEGs a little tighter at best, and the pages come out identical either way.
Can tanko convert CBR to CBZ instead of EPUB?
No, the only output is EPUB. The fixed-layout EPUB is itself a zip with the processed JPEGs under OEBPS/images, but if you specifically need a CBZ, a dedicated archiver is the better tool for that job.
Why does a big CBR pause before the first page appears?
Solid RAR archives have to be decompressed from the start in one pass, so tanko extracts everything up front and then processes pages from memory. The pause is proportional to the archive size; the per-page rate afterward matches a CBZ.
Do my files get uploaded anywhere?
No. Conversion runs entirely in your browser — the file never leaves your device. That's also why there are no size limits or queues.
Is this really free?
Yes. Single-file conversion with every device profile and every option is free, with no sign-up and no watermarks.