PDF Compressor
File ToolsShrink a PDF in your browser, with an honest report when it is already well optimised.
Your files never leave this device. Everything here runs in your browser — your files are never uploaded, stored or seen by us. Open your network tab and check.
Result
Add a PDF to compress it. It is processed here in your browser and never uploaded.
This runs entirely in your browser, which limits what is possible: it cannot resample individual images inside a page while leaving the text vectors untouched, the way a desktop tool like Ghostscript can.
How this is calculated
Light rebuild the document, drop metadata and orphaned objects,
use object streams. Text stays selectable.
Typical saving: 5-20%, sometimes near zero.
Aggressive render every page to a JPEG at the chosen dpi and rebuild
from those images. Text becomes a picture.
Typical saving on scans: 60-90%.How it works
A PDF's size is dominated by whatever is inside it. A scan is a stack of large images, so re-encoding those images makes it dramatically smaller. A text document is mostly font data and vector instructions, which are already compact — there is very little to remove, and no honest tool can make it much smaller without destroying something.
Light mode rebuilds the file: it copies the pages into a fresh document, which drops orphaned objects and revision history, strips metadata such as author and producer, and writes the result using object streams. Text, links and selectability all survive. On a bloated export from a word processor this can save a fifth of the file. On a well-made PDF it can save almost nothing, and when that happens this tool says so rather than reporting a meaningless 2%.
Aggressive mode renders each page to a bitmap at your chosen resolution and rebuilds the document from those images. On a scanned document this is transformative — 60 to 90% reductions are normal. The cost is real and permanent: the text becomes a picture, so it can no longer be selected, searched, or read by a screen reader.
Everything runs in your browser. Nothing is uploaded, which for contracts, bank statements and identity documents is the whole point — those are exactly the files people should not be handing to an anonymous website.
Worked example
A 20 MB scanned document, 12 pages
- light mode 20.0 MB -> 19.6 MB (2% — the images are the size)
- aggressive, 110 dpi, quality 72%:
- each page rendered at 110/72 scale, encoded as JPEG
- 12 pages embedded into a fresh document
20.0 MB → 1.8 MB, a 91% reduction — but the text is now an image
How to use it
- Start with Light. If it gets you under your limit, you keep selectable text and lose nothing.
- If you need more, switch to Aggressive and choose a resolution — 110 dpi is a good balance for reading on screen.
- Lower the image quality further if the file is still too large.
- Download, then open the result and check it is still legible before you send it anywhere.
What this tool does not do
- This is not Ghostscript. It cannot resample embedded images while preserving text vectors — that is precisely the trade-off the two modes expose.
- Aggressive mode destroys text selection, searchability and screen-reader access permanently.
- Encrypted or damaged PDFs cannot be opened.
- Light mode on an already-optimised file will save almost nothing, and will tell you so.
Frequently asked questions
How do I reduce a PDF below 100 KB?
For a scan, use Aggressive mode at 72 dpi and drop the quality to around 50%. For a text document, that size is often not achievable without making it unreadable — the font data has a floor.
Why did my PDF barely get smaller?
Because it was already efficient. A text-based PDF is mostly font and vector data, which is already compressed. When light mode finds almost nothing to remove, the tool reports that honestly instead of pretending.
Will I lose text selection?
In light mode, no — text stays fully selectable and searchable. In aggressive mode, yes: every page becomes an image, so text can no longer be selected, searched or read aloud.
Is my PDF uploaded to a server?
No. The file is read and rebuilt entirely in your browser. This matters more here than for most tools, because PDFs are so often contracts, statements and identity documents.
How is this different from Adobe or Ghostscript?
Desktop tools can resample individual images inside a page while leaving the text vectors untouched — the best of both. A browser cannot reach inside a content stream that way. So we offer the two ends: preserve everything and save a little, or rasterise and save a lot.
What resolution should I choose?
110 dpi reads comfortably on screen and is the default. 72 dpi is smallest and fine for something that will only ever be viewed on a phone. 150 dpi if it may be printed.
Can it compress a password-protected PDF?
Only if it opens without a password. Encrypted files will fail to load, and you will see an error rather than a silent partial result.
Does it work on very large files?
Within your device's memory. A large scan is rendered page by page to limit peak usage, but a several-hundred-page document on a phone may still run out.
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Last updated 3 September 2026.