When a smaller PDF helps
Large PDFs cause friction everywhere. Email servers bounce attachments, online portals reject uploads over a fixed limit, and shared drives fill up. A quick pass through a PDF compressor usually solves the problem without changing how the document reads.
People typically compress PDFs to:
- Attach a scanned contract, lease or tax form to an email.
- Upload a resume, transcript or visa document to an application portal with a strict size cap.
- Send a photo-heavy brochure, catalog or portfolio to a client.
- Archive large batches of scanned paperwork without eating storage.
- Make a report load faster on phones and slow connections.
How the compression works
Most of the weight in a typical PDF comes from photographs and scanned pages. This compressor finds the JPEG images inside your document and re-encodes each one at a lower quality setting. It also scales down any image whose resolution is far higher than the page could ever display. Light caps images at about 200 DPI, Balanced at about 150 DPI and Strong at about 100 DPI.
Everything else stays exactly as it was. Text remains selectable and searchable. Fonts, links, bookmarks and vector artwork are kept. Each replacement image is only used if it is actually smaller than the original, and the finished file is only returned if it beats the size you started with.
Practical tips for the best result
- Start with Balanced. It is the right choice for most scans and photo documents.
- Use Light for print. If the PDF is headed to a professional printer, Light protects image detail.
- Use Strong for screens. For email previews or web uploads where nobody will zoom in, Strong gives the biggest savings.
- Remove what you do not need. Deleting unused pages before compressing often saves more than any setting. Try Delete pages or Split PDF.
- Consider grayscale for scans. A color scan of a black and white letter wastes space. Grayscale PDF can help there.
Private by design
Your PDF is never uploaded. The compressor is code that runs inside your browser, so the file moves from your disk into the tab's memory and back out as a download, and nothing in between touches our servers. That makes it a sensible choice for payslips, medical records and signed agreements. Once the page has loaded, you can disconnect from the internet and it still works. There is no account, no sign-up and no charge.
What this tool cannot do
Compression here targets JPEG photos only. It will not shrink embedded fonts, PNG-style images, or documents that are already well optimized, and it does not convert vector content to images. Password-protected PDFs need their password first, and the saved copy will not be encrypted. The limit is 200 MB per file, and very large documents depend on how much memory your device has.
For related clean-up, Remove metadata strips hidden document properties, and PDF to JPG turns pages into standalone images. If you are combining files before sending, start with Merge PDF.
Frequently asked questions
How do I reduce the size of a PDF for email?
Open the file here, keep the Balanced setting and click Compress PDF. Documents full of photos or scans often shrink enough to fit under typical email attachment limits. If it is still too big, try Strong or split the file into parts.
Will compressing a PDF make the text blurry?
No. Text, vector drawings and fonts are left untouched. Only JPEG photos embedded in the document are re-encoded, so words stay perfectly crisp at any zoom level.
What is the difference between Light, Balanced and Strong?
Light keeps images close to their original quality and saves the least space. Balanced gives a good reduction while photos still look great. Strong lowers image resolution and quality the most, so the file is smallest but pictures look visibly softer.
Why did my PDF barely get smaller?
The savings come from photos stored as JPEG. A PDF made mostly of text, vector graphics, or images saved in other formats has little for the compressor to work on. In that case you will see a note that the file is already optimized.
Can compression ever make my file bigger?
No. If the recompressed version would not be smaller than what you started with, you get your original file back unchanged.
Is it safe to compress confidential PDFs here?
Yes. The document is processed entirely by your browser and never sent to a server. Nobody else can see it, and the tool keeps working without a connection once the page is open.
Can I compress several PDFs at once?
This tool handles one PDF per run. To shrink a set of files as one, combine them first with Merge PDF, then compress the merged document.