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PDF Compressor

Shrink PDF size by re-rendering pages at a controlled resolution and quality.

Compression rasterises pages, so text becomes an image. Use a lower scale for scans, higher for text-heavy documents.

Drag & drop files here

or use the button below · processed locally on your device

Output settings

Free file tool

Free PDF Compressor online

Shrink PDF size by re-rendering pages at a controlled resolution and quality. Use the tool directly in your browser with no sign-up. It supports multiple source files in the same session, so it also works as a free batch tool when you have more than one file.

Free to use

No payment required for this tool.

Batch conversion

Queue multiple source files in one session.

Browser-based

The conversion workflow runs from the web page on your device.

No sign-up

Start the file workflow without creating an account.

What PDF Compressor is useful for

  • Meeting PDF upload-size limits
  • Reducing attachment size
  • Creating a smaller sharing copy of a large document

Input and output checks

Accepted input: Text or settings entered on the page.

  • Open the downloaded output before deleting or replacing the source file.
  • Check the details that matter for your use: page count, dimensions, orientation, text, duration or metadata.
  • For batch jobs, confirm every queued file produced the expected output.
  • If quality or size matters, compare more than one settings combination before choosing the final copy.

How to use this calculator: PDF Compressor

  1. 1Upload one or more PDF files.
  2. 2Choose the render scale and JPEG quality.
  3. 3Start PDF compression and let each page be re-rendered at the selected settings.
  4. 4Review the resulting file size and output quality.
  5. 5Download the compressed PDF.

Worked conversion example

Example: upload a 12 MB source file, choose a moderate quality setting, and run the tool. Exact output size depends on image detail, fonts, pages, duration and codec efficiency; compare the downloaded result visually before replacing the original.

Accepted input
Text or settings entered on the page
Batch behaviour
Multiple files supported

Output settings

SettingExample/defaultEffect
Render scale1.4Changes how the output is encoded or arranged; preview the result before relying on it.
JPEG quality65Changes how the output is encoded or arranged; preview the result before relying on it.

How the browser process works

Shrink PDF size by re-rendering pages at a controlled resolution and quality. The page sends the selected file and settings to its pdf-compress browser engine, creates a new output and downloads it without overwriting the source.

Compression rasterises pages, so text becomes an image. Use a lower scale for scans, higher for text-heavy documents.

Privacy, quality checks and limitations

  • Keep the original file until the downloaded output has been opened and checked.
  • Verify page count, orientation, dimensions, text legibility, audio/video duration and metadata relevant to your use.
  • Browser-local processing reduces routine upload exposure, but your device, browser extensions and download location still matter.
  • A converted preview is not proof of legal authenticity, archival compliance, accessibility or digital-signature validity.

Reduce PDF file size by controlling page render scale and JPEG quality. This is useful when a PDF is too large to upload, email, store, or share easily.

How PDF compression works

The current compressor re-renders PDF pages as images and encodes them with the selected quality. Lower scale and quality can produce smaller files but can also reduce visual detail.

Important PDF compression trade-off

Higher scale / qualityBetter visual detail, usually larger file size
Lower scale / qualitySmaller output, potentially lower visual quality
Text layerThe current compressor rasterises pages, so text becomes part of the page image

Frequently asked questions

How do I compress a PDF?

Upload the PDF, choose the render scale and JPEG quality, then run the compressor.

Does PDF compression reduce image quality?

The current compressor re-renders pages, so lower scale or quality settings can reduce visual quality.

Will searchable text remain searchable?

The current compressor rasterises pages, so text becomes part of the page image.

What settings should I use?

Use higher scale and quality when readability matters and lower settings when reducing file size is the priority.

Is PDF Compressor free?

Yes. The tool is free to use.

Related Guides & Articles

Step-by-step guides for this conversion and related file formats.

PDF to JPG: Complete Guide to Converting PDF Pages into Images

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