Most large PDFs are large because of the pictures inside them: scanned pages, phone photos, high-resolution charts. This compressor opens the PDF in your browser, re-encodes every embedded image at a sensible resolution and quality, and saves a new PDF. The text, links and fonts are left untouched, so the document stays searchable and sharp. Scanned PDFs typically shrink by 60–90%. If you need an exact size for a portal, switch to Target size and the tool works down until the file fits.
What is Compress PDF?
Use our free tool to compress PDF files in your browser, making them small enough to email, upload or archive while the text stays sharp and selectable. Most large PDFs are large because of the pictures inside them: scanned pages, phone photos and high-resolution charts.
The tool rewrites those images at a sensible resolution and quality, leaves text, fonts and links alone, and saves a new PDF. Choose Light, Balanced or Strong, or type an exact target size in KB. Scanned documents often shrink by 60–90%, and you can process a batch of PDFs at once.
How to compress PDF
- Drop one or more PDFs.
- Choose Balanced (best trade-off), Strong (smallest) or Light (best quality), or type a target size in KB.
- Download the compressed PDFs, or all of them as a ZIP.
How Compress PDF works
A PDF is a container of objects. Text is stored as characters plus the fonts needed to draw them, which is compact. Images are stored as separate streams, often at the full resolution of the scanner or camera, even if they appear only a few centimetres wide on the page. In a typical scanned or photo-heavy PDF, those image streams make up almost all of the file size.
Compression works on those streams. Each image is downscaled so its longest side is no larger than a set limit, then re-encoded as JPEG at a set quality. Light keeps up to 2400 px at high quality, Balanced 1600 px, and Strong 1100 px at a lower quality. A grayscale switch removes colour data, which helps further with scanned text.
Because the text layer is not touched, the document stays searchable and copyable. Everything runs in your browser using PDF.js and pdf-lib. CMYK, JPEG 2000 and masked images are left as they are.
Key features of Compress PDF
Free PDF compression
Compress PDF contracts, reports and scans with your free daily runs, with no page limit for normal documents and no watermark stamped on your pages. Drop several PDFs together and download them individually or as one ZIP.
Text stays selectable
On all three levels only the images are recompressed, so your text remains real, searchable and copyable. If a target size forces pages to be flattened, the result line tells you plainly rather than hiding it.
Quick results, no server trip
A typical 10-page scan is processed in a few seconds on your own device, with no waiting for a file to travel to a server and back. Very large PDFs with hundreds of images take longer, depending on your computer or phone.
Works on any modern device
Compress a PDF on Windows, macOS, Linux, Android, iPhone or iPad in current Chrome, Edge, Safari or Firefox. Pick the file from your downloads, email attachments or cloud folder, with no app to install.
Accessible level choices
The Light, Balanced and Strong buttons are labelled and selectable with the keyboard, and the target size field has a clear label. Screen readers hear progress as each PDF is processed, and the page works with zoom and dark mode.
Confidential files stay local
Contracts, bank statements and medical records are processed by PDF.js and pdf-lib inside your browser. They are never sent to our servers, so there is no copy on a server and nothing to trust a deletion policy with.
What makes EZ Compress's Compress PDF different
Images only, text untouched
Many online services print every page to an image, which makes text unsearchable and blurry. This tool recompresses only the embedded pictures, so contracts and reports keep crisp, selectable text.
Exact size when you need it
Switch to Target size and type any limit from 20 KB upward. The tool works through stronger settings until the file fits, flattening pages only as a last resort and telling you when it does.
Never makes it worse
If recompression would not make a file smaller, for example a text-only PDF, you get your original back with a note explaining why, rather than a re-saved file that is the same size or bigger.
Grayscale switch
Turn on grayscale for scanned letters and forms where colour adds nothing. Grayscale images are about a third smaller, which often makes the difference between a file that bounces and one that sends.
Why use Compress PDF?
Email services reject attachments over about 20–25 MB, and many upload forms set far lower limits. A PDF compressor solves both by trimming the image data you do not need. Use it to reduce PDF size before sending a signed contract, to shrink PDF scans for an archive, or simply to make PDF smaller for a shared drive.
It is also a practical PDF size reducer for documents you send repeatedly, such as price lists, menus or brochures. A smaller file opens faster on phones and uses less of your recipients' data and storage.
Who can use Compress PDF?
Lawyers and paralegals
Shrink scanned bundles and signed agreements to email-friendly sizes while keeping the text searchable and the files on your own computer.
Accountants
Compress scanned receipts, statements and year-end packs before sending them to clients or uploading them to tax and bookkeeping systems.
Teachers
Make worksheets and scanned textbook pages small enough for a learning platform or a class email, so students can open them quickly on phones.
Architects and designers
Reduce image-heavy portfolios and drawings with Light or Balanced so proposals stay sharp but small enough to email to clients.
Small business owners
Compress PDF brochures, price lists and invoices so they load quickly on customers' phones and go through email without bouncing back.
Settings explained
| Setting | What it does |
|---|---|
| Compression | Light keeps the most detail, Recommended balances size and quality, Strong gives the smallest file. |
| Or hit a size | Choose between a fixed quality or an exact file-size target. |
| Target size (KB) | The tool finds the highest quality that fits under this size, downscaling only if it must. |
| Convert images to grayscale | Grayscale images are about a third smaller. Good for scanned text documents. |