Tools / PDF Tools

PDF Compressor

Reduce PDF file size in your browser by rewriting the file with compressed object streams.

  1. 1 Upload
  2. 2 Customize
  3. 3 Download

1. Upload

Upload your filesDrag & drop multiple files hereorChoose Files

PDF • Max 20 MB each

Your file stays in your browser when possible. Original language is never translated automatically.

2. Customize

Document settings

Toolora does not translate files. Leave this off to keep Bengali, Arabic, Thai, Chinese, and every other language exactly as uploaded.

The website language does not change your files.

3. Download

How to use

  1. Step 1Choose one or more PDF files (up to 20 MB each).
  2. Step 2Click Compress PDF. The file is rewritten in your browser with compressed object streams.
  3. Step 3Download the result. Check the listed file size — already-optimized PDFs may shrink only a little.

Features

  • Runs in your browser with PDF-lib (file is not uploaded to Toolora servers)
  • Supports multiple PDFs in one session
  • Rewrites the PDF and clears basic document metadata
  • Shows the output file size before you download

Compress a PDF online

Use this tool when a PDF is too large to email, upload to a form, or attach in a chat. Toolora rewrites the PDF in your browser so you can download a smaller (or at least cleaned-up) file without creating an account.

How this compressor works

After you choose a PDF, the page loads it with PDF-lib and saves it again using compressed object streams. Basic metadata (title, author, subject) is cleared and the producer is set to Toolora. This is a structural rewrite, not a photo-quality slider.

Because embedded images are not re-encoded at lower quality, results vary: some files shrink noticeably; others change only a little. Always compare the download size shown after processing.

When to use it

  • A scanned or exported PDF fails an upload size limit
  • You want a quick browser-side rewrite before sharing
  • You prefer not to upload documents to an online service

Limitations

  • Maximum 20 MB per file
  • Encrypted PDFs may fail to open unless the tool can read them
  • Does not offer separate “low / medium / high” image recompression levels
  • Cannot guarantee a target size such as “under 1 MB”

Privacy

Compression runs in your browser. The PDF is not uploaded to Toolora servers for this tool.

Related: PDF File Size Reducer, PDF Merger, PDF Splitter, PDF to JPG, and all PDF tools.

Frequently Asked Questions

What does this PDF compressor actually change?

It reloads your PDF in the browser and saves it again with compressed object streams. It also clears basic metadata fields such as title and author. It does not re-encode embedded images at a lower quality.

Will compression always make my PDF much smaller?

Not always. PDFs that are already optimized, or that mostly contain compressed images, may shrink only slightly. Text-heavy or poorly packed PDFs usually benefit more.

Is my PDF uploaded to your server?

No. For this tool, processing runs in your browser with the PDF library loaded on the page. Your file is not sent to Toolora servers for compression.

What is the maximum file size?

Each PDF can be up to 20 MB. Larger files are rejected before processing.

How is this different from PDF File Size Reducer?

Both tools use the same browser rewrite approach. Use either page; they are linked so you can open the wording that matches your search.