Over the years we have watched developers ask the same questions about zipping files stored in Amazon S3. Here are the ones we see most often, with short answers.
"How do I zip files in an S3 bucket and get a URL?"
Use an API that reads the objects directly from S3 and writes the archive back to the bucket, then return a presigned URL. S3zipper does exactly that — see the zip-and-download guide. (Also asked on Stack Overflow: question 43275575.)
"Can I zip an entire S3 directory?"
Yes. Pass the folder prefix as a file path — for example my-bucket/reports/2026 — and the contents are expanded and compressed recursively. (Related: question 16368119.)
"How do I zip files on the fly without downloading them first?"
Stream them through a zip writer inside the same region as the bucket. The files never need to touch a local disk, and the finished archive lands back in S3. (Related: question 9496459.)
"Why does zipping take so long and use so much bandwidth?"
Because the classic approach downloads every object to the machine that compresses it. Doing the work next to the data removes both the download and the upload step.
"Can I control the zip file name and the expiry of the link?"
Yes — zipFileName sets the name, and expireLink sets how many hours the presigned download URL stays valid.
"What about dynamic files that do not exist when I write the code?"
That is the case S3zipper was built for: the API takes the file list per request, so the contents can be decided at runtime.
More questions? The FAQ has answers on download links, deployment and FileMapper, and you can always contact us.