How to Unzip a File Online Without Installing Software
Someone sent you a ZIP and you are on a computer, or a phone, with nothing to open it. A browser can do it, with some limits that are worth knowing so the result is not a surprise.
Add a ZIP, see what is inside and download one file or all of them. No software to install.
Open a ZIP and take out what you need
- Open ZIP Extractor and add the archive with Select ZIP File, or drop it on "Drop a ZIP file here".
- Wait for "Found 8 file(s) in the archive." The list shows each file with its full path and size.
- Press Download beside a single file, or Download All Files to save everything.
What "Download All Files" really does
This is the part that surprises people. The tool does not give you back an unpacked folder. It starts one separate download for each file, with a 200 millisecond pause between them. For a ZIP with 40 files that means 40 downloads landing in your downloads folder one after another.
- Your browser may ask permission. Many browsers show a prompt such as "allow this site to download multiple files". Allow it, or the later files may be blocked.
- Folders are flattened. The list shows full paths such as
photos/2026/img1.jpg, but each file is saved under its last segment only,img1.jpg. Folder structure is not recreated. - Same names get renamed by the browser. If two folders both hold
notes.txt, the browser will save one asnotes (1).txt. You will have to work out which is which from the list.
If you only need one or two files from a large archive, downloading them individually is the better use of the tool. If you need the whole tree with its folders intact, a desktop unzip program is the right answer.
Why a ZIP will not open
When reading fails you see: "Could not read this ZIP file. It may be corrupted, encrypted, or not a valid ZIP archive." Work through the likely causes:
| Cause | How to tell | What to do |
|---|---|---|
| Password-protected ZIP | Opening on a computer asks for a password | Not supported here; use a desktop program and the password |
| Interrupted download | File is much smaller than the sender says | Download again, check the size |
| Not really a ZIP | Extension is .zip but it is a .rar or .7z renamed | Use the program for that format |
| Multi-part archive | Names like file.zip.001 or file.z01 | All parts need to be joined first; this tool opens only a single ZIP |
An empty archive gets its own message: "This ZIP file appears to be empty." That one is correct behaviour, not a fault.
Look first, then extract
If you are unsure what a ZIP contains, for example because it came from someone you do not know well, look before you save anything. Archive Viewer lists the contents, folders and sizes without giving you files to download. Pay attention to unexpected file types. An invoice that contains a .exe or .js file is a reason to stop. Saving files from an archive and then opening them is the step where trouble starts, and this tool does not scan for malware. The preview approach is explained in how to preview a ZIP without extracting it.
What to do with the files afterwards
- Photos in an odd format can be changed with WebP to PNG or HEIC to JPG.
- A bundle of scanned pages can be turned into one document with images to PDF.
- PDFs that arrived as separate parts can be joined with Merge PDF.
- If you want to send files back as a single archive, create a ZIP online.
On a shared or borrowed computer
Everything you download lands in that computer's downloads folder and stays there after you close the tab. If the files are private, delete them when you are done, and empty the recycle bin or trash as well. Closing the page clears the opened archive from the tool, but it cannot remove files your browser already saved. Also check where the browser saves files, because some are set to ask each time and some use a folder you did not expect. It is a small habit that avoids leaving someone's documents on a library or office machine.
Large archives and phones
The ZIP is opened in your browser's memory, and each file is decompressed only when you press its Download button, or in turn for the Download All Files option. A multi-gigabyte archive on a phone can fail or stall. Try a computer, or extract only the files you need. Mobile browsers also tend to block repeated downloads, so on a phone it is usually best to save files one at a time.
The ZIP is not uploaded. The JSZip library does load from a CDN when the page opens, and the page needs a connection for that, but your archive is not part of the request.
Frequently Asked Questions
Does Download All Files give me a folder?
No. It starts a separate download for each file, and folder paths are not recreated. Each file is saved under its own file name.
Can I open a password-protected ZIP here?
No. Encrypted ZIPs are not supported, and the tool will report that the file could not be read.
Why did my browser block some downloads?
Saving many files in a row can trigger a "download multiple files" permission prompt. Allow it, or download the files one at a time.
What if two files in different folders have the same name?
Each is saved by its final name, so the browser may add (1) to the second. Check the list to see which is which.
Does it open RAR or 7z archives?
No. It reads ZIP files only. A renamed RAR or 7z will fail with the could-not-read message.
Is my ZIP file sent to a server?
No, it is read in your browser. The JSZip library loads from a CDN when the page opens, but your archive is not uploaded.