Prepare a deliberate file set
Select ordinary files with distinct names. Creating a ZIP accepts up to 50 files, 20 MB each and 50 MB total. If two files are both named report.txt, rename one before packing them. This workspace accepts files, not an automatically recursive folder upload; it will not silently invent a folder structure to resolve a collision.
Choose compression for the content
Standard compression is appropriate for text, CSV and many documents. A JPEG or MP3 is already compressed, so a ZIP can be almost the same size or slightly larger. Store without compression is useful when the goal is packaging rather than shrinking. Download the archive and retain the originals until you have checked the result.
Open only a supported archive
Choose Open a ZIP and select one archive up to 20 MB. This tool supports stored/deflated files, UTF-8 names, at most 200 entries and 50 MB expanded. An encrypted, multi-volume, ZIP64 or legacy-encoded archive needs a suitable desktop application. Renaming RAR or 7z to ZIP does not convert it.
Understand the extraction boundary
Structure, path names, expanded sizes and CRC32 checksums are checked before a complete result is returned. Unsafe paths, duplicates and corruption stop the job. The displayed path is retained for identification, but a download uses the final file name only. Two files from different folders can have the same final name; choose suitable save names yourself.
Treat integrity and trust separately
A successful CRC check indicates that extraction agrees with the archive’s stored checksum; it is not an antivirus scan or a verified sender signature. The website never runs an extracted file. Open downloads only when the source and file type are appropriate. Clear the workspace when finished; the original archive and saved downloads stay on your own device.