PDF Compressor - Reduce File Size

Compress and optimize your PDF files to reduce size while maintaining quality

Upload PDF File

Select a PDF file to compress and optimize

Drag & drop PDF file

or click to browse your files

Maximum file size: 50MB

About PDF Compression

Reduce File Size

Optimize PDFs by removing redundant data and compressing images to significantly reduce file size.

Maintain Quality

Our compression algorithms preserve document quality while optimizing file structure.

Fast Processing

Quick optimization process that works efficiently even with large PDF files.

When to Compress PDFs

• Before uploading documents to websites with file size limits
• When emailing PDFs to reduce attachment size and send time
• To save storage space on your device or cloud storage
• When sharing documents in areas with slow internet connections

What the Compressor Actually Does

Most of a large PDF's weight is images, so that is where the tool goes to work. Embedded photos and scans above 150 DPI are downsampled to 150 DPI using bicubic resampling and re-encoded, while the file structure is rebuilt to strip duplicate fonts, unused objects, and leftover data from previous edits. Text and vector graphics are not rasterized; they remain crisp at any zoom level, stay selectable, and stay searchable. Only the resolution of embedded images changes. If the primary engine cannot process a particular file, a lossless structural optimization runs instead, which cleans and deduplicates without touching image quality at all.

Is 150 DPI enough? For anything read on a screen, yes; typical displays render documents at 96 to 110 DPI, so a 150 DPI image still looks identical. Office laser prints of text documents also hold up well. The place it shows is high-quality photographic printing, which wants 300 DPI, so keep your original file as the print master and treat the compressed copy as the one you share.

How much smaller will my file get?

It depends entirely on what is inside. Scanned documents and image-heavy reports routinely shrink by 60 to 90 percent, because scans are usually stored at 300 to 600 DPI with room to spare. A PDF exported from Word or Google Docs that is mostly text may barely change, since there are no oversized images to downsample; if that happens, the tool tells you the file was already well optimized rather than inflating expectations. The success message shows the exact before and after sizes for every run.

Compressing a file

Upload the PDF (up to 50MB). The original size is displayed for reference.
Click Compress PDF. Large scans can take a little while; the button shows progress.
The compressed file downloads as compressed.pdf, and the message reports the percentage saved.

Real limits this solves

Gmail and most corporate mail servers cap attachments at 25MB, which a scanned lease or medical record blows past easily. Government portals, court e-filing systems, and job application sites are stricter still, with 10MB or even 5MB ceilings. And if you archive scanned invoices or receipts month after month, compressing before filing keeps years of records in a fraction of the storage.

Frequently Asked Questions

Is the compression lossless?

Not for images: downsampling to 150 DPI permanently discards pixels, which is where the big savings come from. Text, vector graphics, and layout are untouched. If you need a guaranteed pixel-perfect copy, keep the original file.

Why did my PDF barely shrink?

It was probably already efficient: mostly text, or with images already at or below 150 DPI. Compression cannot remove content that is not redundant, and a second pass through the compressor will not gain anything either.

Will links, bookmarks, and forms survive?

Internal links and bookmarks are preserved in most documents. Be careful with interactive extras, though: fillable form fields can be flattened and cryptographic digital signatures are invalidated by rewriting the file. Compress before signing, not after, and keep the original of any filled form.

Can I compress a password-protected PDF?

No; encrypted files cannot be rebuilt. Remove the password first with the PDF Remove Password tool, compress, then re-protect the smaller file if needed.

Does the text stay searchable after compression?

Yes. Real text layers, including OCR layers in scanned documents, are carried through unchanged, so copy, paste, and search keep working exactly as before.

What happens to my file on the server?

It is uploaded over HTTPS, compressed in a temporary directory, and that directory is deleted as soon as the result is sent back to your browser. Nothing is stored.