Opening tool…
Runs in your browser. Nothing you enter is uploaded to ALCO.
About this tool.
Open a ZIP archive and see what is in it before anything is unpacked — every name, its real size and how hard it was compressed. Tick the files you want and save them one at a time. Each file is checked against the checksum stored with it, so a damaged archive is reported rather than handed to you as a corrupt file. Archives up to 10 MB.
Using this tool.
Can it open a password-protected archive?
No. Encrypted entries are listed and marked, but they cannot be read without the password and this tool does not ask for one. Unlock the archive in a desktop tool first.
Why does it refuse some archives outright?
Because of what its own index says about it. An archive with hundreds of entries, one that expands to far more than it claims, or one entry that swells to hundreds of times its stored size, is refused before a single byte is decompressed — that pattern is how a small file is used to exhaust a browser tab.
What happens to files stored inside folders?
They are saved under a flattened name, because a download cannot create folders. Names carrying "../" or a drive letter are cleaned first, and two files that would end up with the same name are numbered rather than overwriting each other.
Are 7z, RAR or tar archives supported?
Not here — this reads ZIP only, including the deflate and stored methods that make up virtually every ZIP in circulation. Entries using bzip2, LZMA or zstandard are listed and marked as unreadable rather than silently skipped.
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