Add your CPIO file
Drop one or more .cpio files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
CPIO to TAR
Repacking a .cpio archive as .tar moves the same files into a container with different compression and compatibility trade-offs. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
Runs on your deviceConvert supported files
Drop CPIO files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting CPIO archive to TAR archive
Repacking a .cpio archive as .tar moves the same files into a container with different compression and compatibility trade-offs. A .cpio file is a Unix archive of the same vintage as TAR, built from a header-then-data record for each file with no compression and no index. It survives mainly because two things still depend on it: RPM packages and Linux initramfs images.
A .tar file is a tape archive: many files and directories laid end to end in a single uncompressed stream, preserving Unix permissions, owners, and symlinks. It bundles but does not compress — that job is delegated to gzip, bzip2, or xz layered on top. For this route the practical draw is exact preservation of Unix metadata that other archive formats drop and dead-simple, fully streamable structure — balanced against uncompressed on its own, so bare .tar files are as large as their contents, which is worth knowing before you commit a large batch.
Why convert CPIO to TAR?
The practical trigger for this conversion is usually a mismatch: with .cpio, several mutually incompatible header formats share the extension. Switching to .tar buys you exact preservation of Unix metadata that other archive formats drop, which is why it is the better fit for source code distribution across the Unix world. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
CPIO vs TAR at a glance
| Aspect | CPIO archive (.cpio) | TAR archive (.tar) |
|---|---|---|
| Format type | Container — quality depends on the codecs and settings inside | Container — quality depends on the codecs and settings inside |
| How it stores data | the "new ASCII" format (magic 070701) is the modern one: a 110-byte header of hexadecimal ASCII fields, then the filename, then the data, each padded to a four-byte boundary | each file gets a 512-byte header block (name, mode, uid/gid, size, mtime, type) followed by its data padded to 512-byte boundaries |
| Strongest at | extracting the payload of an RPM package | source code distribution across the Unix world |
| Weak spot | several mutually incompatible header formats share the extension | uncompressed on its own, so bare .tar files are as large as their contents |
| Metadata | mode, ownership and timestamps are present in the headers and are read; ZIP output keeps paths and sizes, which are the parts it can represent | records owner and group both by name and numeric id, permission bits, and modification times — extraction as root can restore ownership faithfully |
Pick TAR as the output
Select .tar in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if TAR is selectable, the route is real and validated.
Convert on your device
Press Convert. Extraction and repacking use WebAssembly builds of real archive engines (libarchive and fflate) running in your browser.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid TAR file. Outputs keep the original filename with the .tar extension.
CPIO to TAR questions, answered
Will converting CPIO to TAR lose quality?
Since cpio is container-oriented and tar is container-oriented, the conversion preserves the source content exactly as stored; no additional compression pass is applied beyond what .tar itself requires.
Is it private to convert CPIO files here?
Yes — the .cpio file is processed inside your browser tab and never uploaded. Extraction and repacking use WebAssembly builds of real archive engines (libarchive and fflate) running in your browser. Close the tab and the file is gone from memory.
Where will the TAR file work?
Every Linux distribution, macOS, and the BSDs ship tar as a core utility, and Windows 10 and later include bsdtar at the command line. Graphical tools like 7-Zip open tarballs too, though they may need two passes for compressed variants.
Will the TAR file be bigger or smaller than my CPIO?
It depends on the content: each file gets a 512-byte header block (name, mode, uid/gid, size, mtime, type) followed by its data padded to 512-byte boundaries. Convert one representative file first and compare before batch-processing a large set.
What happens to the metadata in my CPIO file?
In .cpio, mode, ownership and timestamps are present in the headers and are read; ZIP output keeps paths and sizes, which are the parts it can represent. Re-encoding through the browser pipeline does not carry embedded metadata into the output, which doubles as a privacy scrub — check the exported file if you specifically need tags preserved.