Bulk Compress PDF
Bulk Compress PDF reduces the file size of many PDFs in one batch, entirely in your browser — pick a compression level once, watch each file finish live, and download everything as a single zip.
Drop multiple PDFs here, or click to browse
Files are compressed one at a time, in your browser.
How bulk PDF compression works
Instead of opening and compressing PDFs one by one, this tool lets you queue up an entire folder of them and run the same compression setting across all of them in a single batch. Every file is processed directly in your browser's memory using pdf-lib — nothing is ever uploaded to a server, so the batch works the same whether it's five files or fifty.
Files are compressed one at a time, not all simultaneously. Rendering a PDF's pages into memory takes real resources, and doing that for a dozen large files at once is exactly the kind of thing that crashes a browser tab. Processing sequentially — with each file's status updating live in the queue as it finishes — is slightly slower but far more reliable, especially on a phone or an older laptop. You can cancel partway through if you need to, and anything already compressed stays available to download; if a handful of files fail (a corrupted PDF here or there is common in large batches), retrying just those takes one click instead of starting over.
Common use cases
- Shrinking a folder of scanned reports or contracts before long-term archiving
- Compressing a batch of invoices or statements before emailing them together
- Reducing the size of many photo-heavy PDFs before a bulk upload to a portal with a size limit
- Preparing a set of academic papers or filings for submission where per-file size matters
- Cutting storage costs across a large library of older PDFs
Both compression levels here match the single-file Compress PDF tool: light compression keeps text selectable and searchable with a modest size cut, while strong compression rasterizes every page for a much bigger reduction at the cost of selectable text. Results vary per file — image-heavy PDFs shrink the most, while already-optimized text-only PDFs shrink less.
Related tools
Bulk Compress PDF — frequently asked questions
There's no hard limit, but this runs entirely in your browser's memory. We'll warn you if your total selection crosses about 250MB, since very large batches can slow down or strain a low-memory device — splitting into smaller groups works fine if that happens.
Compressing a PDF involves rendering pages in memory. Doing that for many large files simultaneously can crash the browser tab. Processing sequentially — with a live status next to each file as it finishes — is slightly slower but far more reliable.
The batch keeps going. Any file that fails is marked with an error message, and every file that succeeded is still available to download. A "Retry failed files" button re-runs just the ones that failed, without redoing the whole batch.
Yes. A Cancel button is available while it's running — anything already compressed stays available to download, and you can pick up the rest of the batch afterward if you want to.
Yes. Each file shows its own before-and-after size once it's done, and the summary at the end shows the combined total across the whole batch.
Not in a single batch — the compression level you pick applies to every file in that run. Run a second batch if you need a different level for a subset of files.