ZIP Creator & ZIP/RAR Extractor
Create ZIP archives, unzip ZIP files, and extract RAR archives directly in your browser. Large ZIPs can stream directly to disk on supported desktop browsers.
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Selected source files are processed locally in your browser.
Archive Contents
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Extracted Contents
0 filesBrowser-based archive processing: selected files, archive creation, extraction, path normalization, progress reporting, and save preparation are handled locally by browser-side libraries. Source files are not uploaded to a Utiliverse processing server. The page itself loads archive libraries, interface resources, and advertising resources from external providers.
Free ZIP Creator and ZIP/RAR Extractor
The Utiliverse Archive Creator & Extractor focuses on the archive features that can be implemented reliably in a browser: creating ZIP archives, extracting ZIP files, and extracting RAR archives. ZIP creation uses the modern zip.js library, which is designed for large data, streaming, Zip64 archives, and browser file APIs. On compatible Chromium-based desktop browsers, the tool can write the ZIP directly to a file you choose instead of first building the entire archive as one large in-memory object.
RAR creation is not offered in this version. RAR is a proprietary archive format, and reliable browser-side creation is not available through the extraction engine used here. Existing RAR and RAR5 archives can still be opened and extracted. This separation keeps the tool's buttons aligned with what the underlying browser libraries can actually perform.
How to Create ZIP Files and Extract ZIP or RAR Archives
Create a ZIP archive
Choose the Create ZIP tab, then add individual files or select an entire folder. The archive-content list shows the relative paths that will be stored in the ZIP. Folder selection keeps directory structure, which is useful for project files, website folders, documents, backups, and other collections where subfolders matter.
Choose a ZIP filename and compression level. Store-only is fastest and is often sensible for DMG, JPEG, MP4, MP3, and other content that is already compressed. Normal compression is a good general default for mixed files. Maximum compression can take much longer and usually provides limited additional savings on already-compressed source files.
Large ZIP files and direct-to-disk mode
The tool evaluates the combined source size before creation. Under 250 MB is treated as a normal browser workload. From 250 MB through 1 GB, the page recommends a desktop browser and direct-to-disk mode. Over 1 GB is labeled very large because browser, filesystem, memory, and device limits become increasingly important.
If the browser supports the File System Access API, selecting Create ZIP opens a Save dialog first. The ZIP is then written incrementally to that file while each source file is read, which avoids keeping the complete finished ZIP in page memory. This is the preferred path for a file such as a 735 MB DMG. If direct disk writing is unavailable, the tool falls back to building a downloadable Blob; that fallback can still fail with large inputs because the browser must retain more data in memory.
Why a large DMG may not become much smaller
Disk images often contain data that is already compressed. ZIP can still package the DMG successfully, but compression may provide little size reduction. For a large DMG, Store-only or Fast compression can save time and CPU usage. The purpose of ZIP in that case may be packaging, checksum-friendly transfer, or compatibility rather than substantial compression.
Extract a ZIP or RAR archive
Choose the Extract Archive tab and select a .zip or .rar file. ZIP extraction uses zip.js, while RAR extraction uses the browser RAR engine. For password-protected RAR archives, enter the password before extraction. Stored archive paths are normalized before output to prevent parent-directory traversal through entries such as ../file.
Extracted items can be downloaded individually. On browsers supporting direct folder access, Save to Folder recreates subdirectories inside a folder you choose. Extraction still requires browser resources for the extracted data, so extremely large archives can be more demanding than simply creating a streamed ZIP.
Privacy and browser limits
The source files you select are not sent to a Utiliverse upload endpoint. Compression and extraction run in your browser. The page does load its JavaScript/WebAssembly archive libraries from public CDNs. Direct-to-disk ZIP creation is the lowest-memory path available in this browser tool, but no browser-based utility can guarantee an unlimited file size: available RAM, storage space, browser limits, filesystem limits, and device performance still apply.
Archive Methodology, Security Boundaries, and Important Limits
The tool uses zip.js for ZIP creation and ZIP extraction, and a browser RAR engine for RAR extraction. ZIP creation can either stream directly to a user-selected file when the File System Access API is available or fall back to building a Blob in browser memory. ZIP and RAR extraction produce browser-managed Blob objects for the extracted files before they are downloaded or written to a selected folder.
showSaveFilePicker is available, the ZIP writer targets the writable file handle directly instead of assembling the complete finished archive as one Blob first.Worked example: why direct-to-disk matters
Source files: 800 MB total
Direct-to-disk mode:
files → ZIP writer → chosen file on disk
The completed 800+ MB archive does not need to exist as one finished Blob first.
Memory fallback:
files → ZIP writer → in-memory Blob → browser download
This can require much more browser-managed memory and is more likely to fail on large inputs.
Compression level does not guarantee a smaller file
Store-only uses no compression, while levels 3, 6, and 9 request progressively stronger DEFLATE compression. Already-compressed formats such as JPEG, MP4, MP3, many DMG files, and existing archives may shrink very little. Maximum compression can therefore increase CPU time without producing meaningful savings.
Duplicate archive paths replace earlier selections
The create list is stored in a JavaScript Map keyed by the normalized archive path. If two selected files resolve to the same stored path, the later selection replaces the earlier one in the list rather than creating duplicate entries with the same path.
Folder preservation depends on browser-provided relative paths
Folder selection uses the browser's webkitRelativePath value when available. This preserves the selected folder hierarchy inside the ZIP, but support for folder pickers and relative-path metadata varies by browser.
Archive paths are normalized before use
The path sanitizer converts backslashes to forward slashes and removes empty components, ., and .. segments. This reduces parent-directory traversal risk when showing or writing extracted entries. It is still important to review unfamiliar archives before saving their contents.
Extraction is not streamed directly to disk entry-by-entry in all cases
ZIP and RAR extraction currently creates Blob objects for extracted files in browser-managed memory. The Save to Folder action writes those already-extracted Blobs afterward. That means extremely large extracted data sets can exhaust browser memory even when the source archive itself opens successfully.
Password handling is limited to the archive engine's supported formats
The visible password field is passed to the RAR extraction library. The interface does not provide a separate password workflow for encrypted ZIP files. A password-protected or unsupported ZIP may therefore fail to extract depending on what the ZIP library can decode through this implementation.
Archive type is selected mainly by filename extension
The extractor accepts files named with .zip or .rar. It then chooses the RAR path only when the filename ends in .rar; otherwise it uses ZIP extraction. The page does not perform full forensic file-signature detection before choosing the extraction engine.
Large-file thresholds are guidance, not hard limits
The 250 MB and 1 GB messages are user guidance based on the current implementation's memory behavior. They are not guaranteed browser limits. A smaller archive can still fail on a constrained device, while a larger archive can succeed on a capable desktop with sufficient memory, storage, and direct-to-disk support.
Save-to-folder and automatic-download behavior varies by browser
Direct ZIP creation uses the File System Access API when available. Extracted-folder saving uses showDirectoryPicker. Browsers without those APIs fall back to standard downloads, and multiple extracted-file downloads can trigger permission prompts or browser blocking.
Related Utiliverse Tools
Last reviewed: October 2, 2026 · ZIP creation, ZIP64 use, compression levels, direct-to-disk writing, folder-path preservation, path sanitization, ZIP/RAR extraction, password handling, Blob memory behavior, save-folder support, and theme behavior reviewed against the current implementation.
Archive Tool FAQ
Can this tool create RAR files?
No. This version creates ZIP files and extracts ZIP or RAR archives. RAR creation was removed because the browser extraction engine does not provide a dependable RAR-writing path.
Can it create a ZIP from a 735 MB DMG?
On a compatible Chromium-based desktop browser, the direct-to-disk ZIP path is designed to handle large inputs more reliably because the finished ZIP is streamed to the chosen file instead of being assembled completely in page memory. Actual success still depends on free disk space, browser limits, device resources, and the source file.
What size warning does the tool use?
Under 250 MB is shown as a normal workload, 250 MB through 1 GB is marked large with a recommendation to use a desktop browser and direct-to-disk mode, and more than 1 GB is marked very large and device dependent.
Can it unzip ZIP files?
Yes. Select a ZIP archive in Extract Archive mode to read and extract its files directly in the browser.
Can it unrar RAR files?
Yes. RAR and RAR5 archives can be opened and extracted in the browser, including password-protected RAR files when the correct password is supplied.
Are my source files uploaded?
No. Selected source files and archives are processed locally by the browser-side archive libraries rather than uploaded to a Utiliverse server.
Can I preserve folders inside a ZIP?
Yes. Folder selection preserves relative paths during ZIP creation, and Save to Folder can recreate extracted subfolders on supported browsers.
Why can very large extraction still fail?
Extraction may hold one or more decompressed files in browser-managed memory before they are downloaded or saved. Very large archives can therefore exceed the memory available to the tab even though ZIP creation can stream directly to disk.
What happens if two selected files have the same archive path?
The create list is keyed by normalized archive path, so the later selection replaces the earlier file at that same path.
Does Maximum compression always make the smallest ZIP?
Not necessarily. Already-compressed files may shrink very little, so a higher compression level can take more CPU time without meaningful size savings.
Does extraction make files safe to open?
No. Archive extraction only unpacks the files. Executables, scripts, documents, installers, and other extracted content can still be malicious.
Can encrypted ZIP files be opened with the password field?
The visible password field is passed to the RAR extraction path. Encrypted ZIP support depends on the ZIP library and this implementation does not provide a dedicated ZIP-password workflow.
How does the tool decide whether an archive is ZIP or RAR?
The selected filename must end in .zip or .rar. Files ending in .rar use the RAR engine; the other accepted archive path uses ZIP extraction. The tool does not perform full file-signature forensics first.