What PDF Compress helps you do

Reduce a PDF's size locally with a lossless re-save or one of three raster quality modes. The result includes the before-and-after size so you can choose whether the reduction is worth any change in searchability or visual quality. It is the practical pass before an upload limit, an email cap or a slow connection.

The PDF is read, re-saved or rasterized in your browser. No document is uploaded to Haivix, and no compressed copy is kept on a server.

How it works

Lossless mode loads the document with a JavaScript PDF library and saves it again with object streams, which can remove structural overhead without rasterizing text. Raster modes render each page in a worker, encode it as a JPEG at the chosen quality, and rebuild the PDF with one image per page. That is why raster output is smaller but no longer selectable or searchable.

How to use PDF Compress

Load the PDF and note its current size.
Try Lossless first to preserve page content while reducing structural overhead.
If the file remains too large, use Balanced raster mode and inspect text and diagrams in the result.
Compare the before and after sizes, then download the version that meets the limit.
Keep the original document for any future edit or accessible version.

When to use it

Get a report under an email or portal upload limit.
Shrink a scanned document that is mostly images.
Reduce a PDF before sending it over a slow connection.
Prepare a preview copy that does not need selectable text.
Test how much structural overhead a text-native PDF carries.
Make a lighter attachment for a mobile reader.
Fit a portfolio or deck into a form with a fixed maximum size.

When not to use it

Do not rasterize a document that must remain searchable, selectable or accessible.
Do not compress a signed PDF if the signature must stay valid.
Do not use it to repair a damaged or encrypted file; fix the source first.

Example

A 14 MB scanned lease needs to fit a 5 MB portal limit. Lossless mode saves only a few hundred kilobytes, so Balanced raster mode is used instead. The pages stay readable for review, the file drops under the limit, and the original stays on disk for the signed copy. If the portal also requires a preview thumbnail, the high-quality mode is a better trade than the smallest one.

What you can do with PDF Compress

Re-save a PDF with object streams for a lossless optimization attempt.
Rasterize pages at high, balanced, or smallest-size JPEG quality.
Show page-by-page progress for raster compression.
Compare original and output sizes before using the downloaded result.
Keep the work in the browser, with no upload queue.
Choose the mode that matches the document's use.

Example: fit a document under an upload limit

Try Lossless first because it preserves page content and may reduce structural overhead. If the file remains too large, use Balanced raster mode and inspect text, signatures, diagrams, and small print in the downloaded PDF.

Move to the smallest mode only when file size matters more than perfect detail. Keep the original document because raster compression can turn selectable text and vector artwork into page images.

For a scanned document, raster mode often produces the largest saving because the pages are already images. For a text-native report, lossless is usually the better first attempt.

Check the output on the device the recipient will use. A file that is readable on a large monitor may be uncomfortable on a phone, especially in the smallest raster mode.

What to know before you start

Already optimized PDFs may shrink very little or even become slightly larger.
Raster modes can reduce sharpness, remove text selection, and affect accessibility or searchability.
Password-protected or damaged PDFs may need another workflow before compression succeeds.
Raster output is a new PDF made of page images; it is not a repair or an OCR pass.

Common mistakes

Choosing raster mode first and losing selectable text unnecessarily.
Assuming every PDF will shrink; some are already efficiently packed.
Compressing a signed document and invalidating the signature.
Not checking small print, tables or diagrams after raster compression.
Overwriting the original instead of keeping a clean copy.
Using the smallest mode for a document that will be printed at full size.
Compressing an encrypted PDF without unlocking it first.

Troubleshooting

If lossless mode makes the file slightly larger, the source was already optimized. Try a raster mode only if the document does not need to stay searchable.

If raster output looks blurry, use the high-quality mode or keep the original resolution. The smallest mode favors size over legibility.

If the browser runs out of memory, split the PDF into smaller sections first, then compress each part.

If the file cannot be opened, it may be encrypted or damaged. Unlock or repair it before compressing.

If text is no longer selectable, the file was compressed in a raster mode. Use the original for any copy that must remain searchable or accessible.

If the result is larger than the original, keep the original. Re-saving a compact file can add overhead without a meaningful saving.

PDF Compress