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Compress PDF Files to a Smaller Size

Make a PDF smaller for an upload limit or an email. Start with the safe lossless option, which only tidies the file structure, or recompress the JPEG images at light, balanced or strong settings. The tool measures the real before and after sizes, tells you how many images it changed and why it skipped the others, and shows page 1 before and after so you can check the quality. If a file cannot be made meaningfully smaller it says so instead of offering a pointless download.

Files are processed in your browser and are not uploaded.

Drag and drop here, or choose a file. Up to 100 MB.

How should it be compressed?
Or aim for a size limit

For upload portals with a limit such as 2 MB. It tries lossless first, then stronger image settings, and stops at the first result that fits.

Page text is never turned into pictures, so it stays selectable. Lossless mode changes no image. The image options re-save only JPEG images that are safe to change, can slightly reduce quality, and report what they did. The size reduction is measured, never promised: text-only files may not shrink at all.

Good to know

  • Scans and photos are usually the big part of a large PDF. Only JPEG images are recompressed; other image types are reported as skipped.
  • Images with transparency, unusual colour formats or a rotation flag are left alone so they do not change appearance.
  • Colour profiles in recompressed images are converted to standard RGB, which can shift colours slightly.
  • Need only some pages first? Use the splitter, or combine files with the merger.

How it works

  1. Choose a PDF. A lossless optimization runs straight away.
  2. To shrink images, choose Light, Balanced or Strong and press Optimize with this setting. Or enter the size limit of your upload portal and press Compress to fit.
  3. Read the sizes and the note about how many images were recompressed or skipped.
  4. Compare page 1 of the original and the result, set the output name, and download.

Options explained

Lossless (safe)
Rewrites the file structure only. Text stays selectable and images are untouched. Often saves little.
Light, Balanced, Strong
Re-save JPEG images at up to 2400, 1600 or 1200 pixels and 85%, 70% or 50% quality. Smaller files, more visible quality loss.
Aim for a size limit
Enter a limit in MB. The tool tries lossless, then Light, Balanced and Strong, and stops at the first result that fits. If none fits it shows the smallest result and says it could not reach the limit.

How the result is worked out

  • Only JPEG images are re-encoded, and only when it is clearly safe. Images with transparency, unusual colour formats, a custom colour mapping or a rotation flag are left alone and reported.
  • A recompressed image replaces the original only if it is at least 5% smaller. Colour profiles in recompressed images are converted to standard RGB.
  • After saving, the result is reopened to confirm it is a valid PDF with the same page count.

Example

A one-page PDF containing a large photo and a small PNG logo: Balanced recompresses the photo to 1600 pixels at 70% quality, skips the PNG as “not a JPEG image”, and reports the size reduction.

Tips for better results

  • Scan-heavy and photo-heavy PDFs may not shrink, because this tool does not reduce image quality.
  • Compare the original and optimized sizes before downloading. A download is offered only when the file got smaller.
  • For larger savings, re-export from the original document with lower image quality or rescan at a lower resolution.

Limitations

  • No fixed reduction is promised. Text-only PDFs may not shrink at all, and the tool says so.
  • Signed PDFs lose their signature when rewritten, and forms may change. The tool warns about both.
  • Text is never turned into pictures, so it stays searchable, but scans stored as non-JPEG images cannot be recompressed here.

Guides that go with this tool

Frequently asked questions

Why did my PDF not get smaller?

Its size is probably in images that this tool cannot change (not JPEG) or it is already efficient. The message explains which.

Will quality suffer?

Lossless mode changes no image. Image compression lowers quality as you choose, and shows page 1 so you can judge.

Can I compress a PDF to under 2 MB?

Enter 2 as the size limit and press Compress to fit. It works when the size is in JPEG images. If it cannot reach the limit it says so and shows the smallest result it could make.

Is my file uploaded?

No. Compression happens in your browser.

Does it work on scanned documents?

If the scans are JPEG images, yes. Other formats are reported as skipped.

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