Convert RAR to TAR Online (Getting RAR Content Into an Uncompressed Linux-Native Container)

Plain Tar Has No Compression Built In at All, Unlike Every RAR Archive

Tar — short for "tape archive," dating back to Unix's early 1970s magnetic-tape backup tools — bundles files together using simple 512-byte header blocks that record each entry's name, owner, permissions, and size, one after another in sequence. It has no compression stage of its own whatsoever; a plain .tar file is exactly as large as the sum of the files inside it, plus a small amount of header overhead. Every RAR archive, by contrast, always runs through RARLAB's proprietary compression algorithm, since RAR was designed from the outset as a compressed archive format, not a plain bundling one. Converting RAR to tar means fully decompressing the RAR's proprietary encoding — a step that requires either WinRAR or a tool licensed under RARLAB's extraction-only unRAR terms — and then rebuilding the recovered files inside tar's uncompressed header-and-data structure.

That trade is a deliberate design difference, not a missing feature on tar's part: tar was built to be paired with a separate compressor bolted on afterward, which is exactly why .tar.gz, .tar.bz2, and .tar.xz all exist as two genuinely separate steps rather than one combined format. RAR bundles its own proprietary compression directly into the same container that groups the files, so there's no equivalent "just the bundling, no compression" option available from RAR alone the way plain tar offers.

Tar's format has also gone through its own standardization, most notably in the POSIX.1-2001 ustar and later pax variants, which extended the original header fields to support longer filenames and additional metadata without changing the basic block-based layout. RAR, by comparison, has no equivalent open standards body governing its structure at all — RARLAB alone decides what changes between one version of the format and the next, which is why RAR4 and RAR5 differ as much as they do while remaining under the same company's sole control.

Unix Ownership and Permission Bits Are a Native Part of Tar, Not an Extension

Tar's own header format was built specifically for Unix systems, so it stores numeric user and group ownership IDs, full Unix permission bits (read, write, execute for owner, group, and others), and symbolic link targets directly as core fields every tar reader understands, without any optional extension needed. RAR does track file attributes internally too, but its own metadata handling is proprietary and tool-dependent in the same way its compression is — how faithfully those attributes translate depends on which specific software extracted the RAR file to begin with, since there's no openly published specification governing exactly how RAR stores them.

This matters concretely for anyone extracting a RAR archive that originated on Linux and needs the files to behave correctly once tarred back up on a Linux system — a script marked executable, or a file owned by a specific service account, is far more reliably preserved through tar's native, standardized header fields than left dependent on how a particular RAR-extraction tool happened to interpret RARLAB's proprietary attribute storage.

What Converting RAR Content to Plain Tar Actually Trades Away

• Lose — all of RAR's compression: plain tar has no compression stage at all, so the resulting archive is typically much larger than the original RAR.
• Gain — a format that's freely creatable by anyone: tar is documented, open, and has no licensing restriction anywhere close to RARLAB's extraction-only unRAR terms.
• Gain — native Unix permission and ownership fields: tar's header stores this data as a standard part of every entry, not as tool-dependent proprietary metadata.
• Lose — RAR5's Reed-Solomon recovery record: plain tar has no equivalent built-in error-correction feature for repairing a damaged archive.
• Lose — RAR's optional password encryption: plain tar carries no encryption of its own; protecting a tar archive means adding a separate step like GPG afterward.
• Gain — a natural staging point for further compression: the resulting tar can still be piped into gzip, bzip2, or xz afterward, exactly the same way any other tar archive would be.

Where Tar Ships by Default Compared With Where RAR Support Has to Be Added

Tar is preinstalled on essentially every Linux distribution and on macOS's command line, since GNU tar or BSD tar has shipped as a base system utility for decades. RAR support, on the other hand, is never bundled the same way: Windows Explorer only gained native RAR extraction with the 24H2 update in 2024 (using the open-source libarchive library, and only for unencrypted archives), macOS's Archive Utility has no RAR support whatsoever, and most Linux distributions need the unrar or unar package installed separately before a .rar file can be opened at all.

Because tar itself carries no compression, extracting a RAR archive and rebuilding it as plain tar is a genuinely useful staging step specifically on systems built around Unix tooling that don't already have RAR support installed — the resulting tar then behaves exactly like any other tar archive for every subsequent step, including compressing it afterward with whichever tool the target environment already has on hand.

This also matters for automated pipelines that expect a plain tar as input: build systems, container image tooling, and package-creation scripts on Linux very commonly assume tar as the universal intermediate format, and content still locked inside a RAR archive has to pass through this exact decompress-then-retar step before it can plug into that kind of tooling at all.

Documented Problems Specific to Moving RAR Content Into Plain Tar

A recurring, documented complaint is a resulting tar archive turning out unexpectedly large compared with the original RAR file — this isn't a conversion error; plain tar genuinely applies no compression at all, so an archive that was previously shrunk by RAR's algorithm returns to something close to its original uncompressed size once rebuilt as tar, and a further compression step is needed afterward if a smaller file matters.

A second common issue involves symbolic links inside the original RAR archive not surviving the conversion as working links — whether they do depends heavily on which specific tool extracted the RAR first, since RAR's own symlink handling is proprietary and inconsistently implemented across different extraction tools, unlike tar's native and standardized symlink field that every compliant tar reader honors the same way.

A third pattern involves multi-volume RAR archives specifically — every .part001.rar, .part002.rar volume in the set has to be present before extraction can even begin, since RAR5's splitting scheme distributes the archive's internal structure across the complete set of volumes rather than keeping each one independently readable, so a conversion attempted with one volume missing fails outright instead of producing a partial tar.

A fourth issue involves very long file paths inside the original RAR archive running into limits in older tar implementations — classic ustar headers cap filenames at 100 characters in their original field, and while modern GNU tar and pax-format extensions handle much longer paths without trouble, a conversion pipeline built around an older or stripped-down tar tool can silently truncate or reject deeply nested paths that the RAR archive itself had no trouble storing.

RAR's Compressed Container Against Tar's Plain One

Questions About Converting RAR Content Into a Plain Tar Archive

Why is the tar file so much bigger than the original RAR?
Because plain tar has no compression stage whatsoever — it only bundles files together, so an archive that RAR's algorithm previously shrunk returns to close to its original size once rebuilt as tar.

Can I compress the resulting tar file afterward?
Yes. A plain tar can be piped into gzip, bzip2, or xz just like any other tar archive, producing a .tar.gz, .tar.bz2, or .tar.xz file with compression added back on top.

Will Unix file permissions from the RAR survive the conversion?
It depends on the tool that extracted the RAR first, since RAR's attribute handling is proprietary and inconsistent across extractors — but once the files reach tar, its native permission fields preserve them reliably from that point on.

Do I need every volume of a multi-part RAR to convert it?
Yes. RAR5's split-volume scheme spreads the archive's structure across the entire set of .part001.rar, .part002.rar files, so extraction fails if any volume is missing.

Why convert to tar instead of just extracting the RAR normally?
Tar is a standard, freely creatable container already preinstalled on Linux and Unix systems, useful when the goal is getting content into a format those systems' own native tooling handles without depending on RAR-specific software at all.