Free online RAR to ISO converter

Some disc-burning programs, virtual drives, installers, and game or operating-system tools require an ISO rather than a RAR archive. The usual conversion is to extract the RAR and author an ISO from its files; if the archive already contains an ISO, extract that image instead.

What the RAR format is

RAR is a compressed archive format designed by Eugene Roshal and commonly created with WinRAR or compatible archive software. It stores files and folders in one container and supports compression, password-based encryption, recovery records, comments, and split volumes such as backup.part1.rar, backup.part2.rar, and later parts.

Large downloads, backups, software packages, and compressed disc-image distributions commonly use RAR. A RAR file is not normally a disc image; it does not automatically contain the filesystem, boot sectors, or other structures expected by disc software. 7-Zip and PeaZip can extract RAR archives, while WinRAR can also create them.

What the ISO format is

ISO is a single-file image of an optical-disc layout. Depending on how it was authored, it can contain an ISO 9660 filesystem with extensions such as Joliet or Rock Ridge, a UDF filesystem, or boot information associated with the original disc.

Operating systems can mount many ISO files as virtual discs, and disc utilities can write them to CD, DVD, or Blu-ray media. An ISO keeps the disc directory structure in one image and can preserve boot metadata when the original image is retained. It normally does not provide RAR-style compression, so an ISO rebuilt from extracted files is often close to the uncompressed source size.

Check the archive before converting

1. Put all volumes in one directory. Open the first file, such as package.part1.rar or package.rar, with 7-Zip or WinRAR; do not open a later volume as a separate archive.
2. List the contents. If the archive contains an .iso file, extract that file with 7-Zip → Extract or the equivalent WinRAR command and use it directly. Rebuilding it can discard its boot sectors, volume metadata, or filesystem details.
3. If the archive contains ordinary folders and files, extract them and create a new ISO. Names such as BOOT or EFI do not by themselves prove that a newly authored image will boot.

Convert it on Windows

1. Right-click the first RAR volume and select 7-Zip → Extract files. 7-Zip reads the other volumes automatically when they are present, correctly named, and undamaged. Enter the password if prompted.
2. Open an ISO authoring application such as AnyBurn or PowerISO and choose its option for creating an image from files or folders. Add the contents of the extracted directory, not an unnecessary outer directory, unless that directory was part of the intended disc layout.
3. Select a filesystem supported by the destination: ISO 9660 with Joliet for broad compatibility, or UDF when the target requires it or the files exceed ISO 9660 limits. Choose an output filename ending in .iso and create the image.
4. Mount the result or open it with 7-Zip and check the directory structure and important files before burning it. This check does not prove that a reconstructed image is bootable.

Microsoft's oscdimg, included with the Windows Assessment and Deployment Kit, is a command-line alternative. A basic image can be created with:

oscdimg -m -o extracted output.iso

The -m option permits an image larger than standard CD capacity, and -o optimizes duplicate files. Creating bootable installation media requires the correct source boot image and firmware-specific options; a folder-to-ISO command alone is insufficient.

Convert it on Linux or macOS

Extract the first volume with 7-Zip:

7z x archive.part1.rar -oextracted

On Linux, create an ISO with xorriso:

xorriso -as mkisofs -o output.iso -r -J extracted/

The -r and -J options add Unix-style and Windows-compatible filename handling; they do not recreate boot metadata. Mount the image or inspect it with 7z l output.iso.

On macOS, an installed RAR-capable extractor can be followed by:

hdiutil makehybrid -o output.iso extracted/

Open the resulting image in Finder and compare its contents with the extracted source. For a bootable image, use the original boot image and the authoring options required by the target firmware or operating system.

Use the built-in online converter

You can convert the archive on 101convert.com for free without installing software: upload the RAR, wait for processing, and download the ISO. Browser-based processing is less suitable for very large, encrypted, confidential, or split archives; all required volumes and the archive password may be needed.

Quality and compatibility limits

• Extracting an embedded ISO preserves the original image. Rebuilding an ISO from files preserves their contents but may change filename rules, permissions, timestamps, directory metadata, boot sectors, multisession data, copy-protection structures, and console-specific layouts.
• A folder containing boot files is not automatically bootable. Bootability depends on the original boot image, partition or El Torito metadata, filesystem, and BIOS or UEFI requirements.
• Missing or damaged RAR volumes prevent reliable extraction. Recovery records can repair some damage only when the archive creator included them.
• Check the destination's supported filesystem, boot mode, filename limits, and maximum image size before authoring. For an expected original image, compare a publisher checksum with sha256sum output.iso on Linux or Get-FileHash output.iso -Algorithm SHA256 in PowerShell.