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PDF Compressor

Shrink a PDF's file size by re-encoding its pages at a chosen quality and resolution. See the size before and after, preview the result, and tune the quality until size and readability balance.

Everything runs locally in your browser. Your data never leaves your device.

Upload

Drop a PDF here

It gets re-encoded at your chosen quality. Click to choose a file.

It never leaves your browser.

Compression

This mode turns every page into a picture of itself. The file gets much smaller, but text stops being selectable and searchable. Use the lossless re-save to keep text intact.

70

Lower saves more space, higher keeps pages crisper.

150 DPI

100 to 150 DPI reads fine on screens, 300 DPI holds up in print.

Next steps

Send this tool's output straight into another tool.

Hash text or a file with MD5, SHA-1, SHA-256, SHA-512, SHA-3, BLAKE2, BLAKE3, CRC32 and more, all computed live as you type. Compare against an expected checksum and copy any digest.

Verify a checksum online: drop a file, paste the expected checksum and see instantly whether they match. The hash type is detected from the checksum itself, covering MD5, SHA-1, SHA-256, SHA-512, BLAKE3, CRC-32 and more, and sha256sum lines or whole checksum files can be pasted as-is.

Compress text or a file with gzip, deflate, brotli or Zstandard and see the size before and after, the compression ratio and how long it took. One click tries every method and recommends the smallest result.

Decompress gzip, deflate, brotli or Zstandard data from a file or pasted Base64 and read the result as text or download it. Detects the format from the magic bytes where possible, with a manual override.

Inspect any file or text as a hex dump with offsets, byte values and an ASCII column. Jump to an offset, search for bytes or text, select a range to see it decoded as integers and strings, and copy or download the dump.

Combine several PDFs into one or split a PDF into separate files. Reorder pages with drag and drop, see a thumbnail of every page, extract a page range or pick single pages, and download the result.

Render every page of a PDF as an image. Choose PNG or JPEG, set the resolution, pick single pages or a range, then download pages one by one or all at once as a zip.

Shrink a PDF's file size by re-encoding its pages at a chosen quality and resolution. See the size before and after, preview the result, and tune the quality until size and readability balance.

Encrypt any file with a password using AES-256-GCM, or decrypt a file that was encrypted here. Strong key derivation and integrity protection built in.

About the PDF Compressor Tool

This tool makes a PDF smaller. The main mode re-encodes every page as a JPEG at a quality and resolution you pick, which is how most in-browser PDF compressors work. A second, lossless mode rewrites the file structure without touching the content.

You see the size before and after, the percentage saved, and a page by page preview of the result, so you can tune quality against readability before downloading.

What you can do

  • Compress a PDF that is too big for an email attachment.
  • Reduce a PDF's file size with quality and resolution sliders.
  • Compare the file size before and after compression.
  • Preview every page of the compressed file.
  • Try a lossless re-save that keeps text selectable.

How to use the PDF Compressor

  1. 1Drop a PDF onto the upload area.
  2. 2Pick the page compression mode or the lossless re-save.
  3. 3Adjust quality and resolution until size and readability balance. The result updates as you move the sliders.
  4. 4Check the preview, then download the compressed file.

The honest trade-off

The page compression mode turns each page into a picture of itself. That is what makes the file so much smaller, but it also means the text can no longer be selected, searched or copied. If the text has to stay live, use the lossless re-save instead and expect smaller savings, since it only rewrites the file structure and the result depends entirely on how the original was written.

When it does not get smaller

A PDF that is already efficiently compressed, for example one that is mostly photos at a sensible quality, can come out the same size or larger. The tool warns you when that happens. Lower the resolution or quality, or keep the original.

Send the result onward

Need the pages as standalone pictures instead? The PDF to Images exports them as PNG or JPEG at any resolution.

Credits

Open source does the heavy lifting in this tool. Thank you to:

  • pdf-lib

    A library for creating and modifying PDF documents in pure JavaScript.

  • PDF.js

    Mozilla's PDF renderer, the same engine that displays PDFs in Firefox.

Everything this site builds on is listed on the credits page.

Compress text or a file with gzip, deflate, brotli or Zstandard and see the size before and after, the compression ratio and how long it took. One click tries every method and recommends the smallest result.

Decompress gzip, deflate, brotli or Zstandard data from a file or pasted Base64 and read the result as text or download it. Detects the format from the magic bytes where possible, with a manual override.

Turn photos and images into a single PDF. Drop in JPEG, PNG or WebP files, reorder them, pick the page size, orientation and margins, and choose whether each image fills the page or keeps its own size.

Shrink any image with as little quality loss as possible. Pick a WhatsApp, Instagram or Discord preset, or switch to Custom to hit a hard file size or a fixed quality, downscale with aspect-locked resolution sliders, and keep or strip EXIF metadata. Live preview, multiple images at once.

Combine several PDFs into one or split a PDF into separate files. Reorder pages with drag and drop, see a thumbnail of every page, extract a page range or pick single pages, and download the result.

Render every page of a PDF as an image. Choose PNG or JPEG, set the resolution, pick single pages or a range, then download pages one by one or all at once as a zip.