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Document Utility

PDF Compressor

Reduce PDF file size by adjusting image quality and rendering resolution. Compress PDFs directly in your browser before sharing documents, attaching files to email, or uploading them to a website.

Browser Compression Process PDF files directly in the browser without saving them on the server during normal use.
Compression Options Adjust compression level, image quality, rendering resolution, and page range based on your needs.
Size Comparison Check original size, compressed size, saved size, and reduction rate at a glance.
File Not selected
Quality Recommended
Pages All
Status Ready

PDF Compression Settings

Upload a PDF file, then choose compression level and image quality. This works best for scanned documents, image-heavy PDFs, and captured materials.

PDF Upload

Drag & Drop or

Drag a PDF file into this area or upload it using the select file button.

Notice This tool renders PDF pages as images, compresses them, and rebuilds a new PDF. It is usually more effective for scanned documents, photo PDFs, and image-heavy PDFs than text-only PDFs.

A stronger setting may reduce file size more, but text or images may become blurry.

JPG has broad compatibility, while WebP may produce smaller files depending on the browser environment.

To keep document contents readable, try Recommended or High quality first.

Higher resolution makes the result clearer but may increase the compressed file size.

The .pdf extension is added automatically when saving.

Leave this empty to compress all pages. Enter a range when compressing only selected pages.

Before Compression

For important contracts, certificates, or submission documents, test with a copy first and compare the original with the result.

Because of the compression method, original PDF features such as text selection, links, annotations, and bookmarks may not be preserved.

Recommended Compression Presets

Quickly apply compression settings based on your purpose, such as email attachment, scanned document, quality-first, or maximum compression.

Compression Status

Check PDF selection, compression progress, and size comparison results after completion.

Ready
Please select a PDF file.
Practical guide

Compress a PDF and check page quality

Turn PDF pages into a new image-based PDF in your browser. Choose JPG or WebP, resolution and a page range, then compare the actual file size. Scanned pages may shrink, while a compact text PDF can become larger.

Prepared & reviewed by
win-j
Last reviewed
2026-09-30

Who this helps

  • People preparing scanned documents for upload
  • People comparing file size and readability

When to use this tool

  • Create a smaller sharing copy of a scan
  • Keep only selected pages in the output

From input to a checked result

  1. 1

    Select a PDF while keeping the original.

  2. 2

    Start with Balanced: JPG, quality 0.76 and scale 1.5.

  3. 3

    Leave the page range empty for all pages, or enter 1-3,5.

  4. 4

    Compress, compare file sizes and inspect small text before downloading.

Example 1

Keep selected pages

Input
5-page PDF; range 1-3,5
Result
4 output pages: 1, 2, 3, 5

Repeated page numbers are removed and output is sorted by original page number.

Example 2

Change image resolution

Input
A4 page, 595 × 842 pt; scale 1.5
Result
892 × 1263 px raster; PDF page stays 595 × 842 pt

Scale changes image resolution, not the physical paper size. Actual A4 dimensions can contain decimals.

How it works

PDF.js draws pages onto a canvas and jsPDF inserts each image into a new PDF. Light uses quality 0.88 and scale 1.8, Balanced 0.76 and 1.5, and Strong 0.62 and 1.2. Page ranges include both endpoints; invalid or out-of-bounds ranges are rejected.

Limitations

  • Searchable text, links, forms and accessibility structure are not preserved by page rasterization.
  • Smaller output is not guaranteed. Check fine print and image quality.
  • Large, protected or damaged PDFs may fail. Keep the original signed document.
Your data

The selected PDF and generated file are processed in this browser and are not uploaded to the win-j conversion server.

Frequently asked questions

Why can I no longer select text?

Each page is rebuilt as an image. Keep the original when text search, copying or links are needed.

Will Strong always give the smallest file?

No. Compare the downloaded size; an already optimized PDF may become larger.

Can I reorder pages using 5,1?

The output is sorted by original page number, so this produces pages 1 and 5. Use the merge and split tool to arrange documents.