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1 · Choose the PDFs
Pick one file or many. Large books take a few minutes; leave the tab open while they run.
Now choose the quality below, then press Optimize.
2 · Choose the quality
Pages are re-rendered at the chosen resolution and re-compressed. Lower settings mean smaller files.
3 · Results
Each finished file can be downloaded on its own, or all together as a ZIP.
| File | Before | After | Saved | Status | |
|---|---|---|---|---|---|
| No files yet. | |||||
Nothing gets worse: every file is tried two ways — rebuilt as images, and cleaned up with the text kept —
and you get whichever came out smallest. If the original is already smaller than both, the tool says so and leaves it alone.
How it works: each page is redrawn at the chosen resolution and saved as a compressed image, which is what
makes picture-heavy books so much smaller. The text in the optimised file becomes part of the picture, so it can no
longer be selected or searched. If you need the text to stay live, tick Keep text selectable — the saving
is then much smaller. Always keep your original print PDFs.
Prefer the Windows version?
Jessi PDF Web Optimizer v5.1 — runs on your PC with Ghostscript, for very large batches.