PDF · Local utility

PDF Compressor

Shrink a PDF by optimizing its structure or re-encoding pages as JPEGs.

Runs locally · Nothing is uploaded

LOCAL PDF STUDIO

PDF Compressor

Shrink a PDF two honest ways: optimize its structure, or strongly compress every page as an image — all without an upload.

01 / Source

Choose one PDF and a compression mode

Max 500 pages

Choose one PDFUp to 30.0 MB

Compression mode

Optimize structureStrong compression

Removes document metadata and rewrites the file structure. Text stays selectable and searchable, but the size reduction is usually limited.

02 / Result

Compressed PDF

Awaiting run

No compressed PDF yet

Choose a PDF and a mode, then compress. The before-and-after sizes are shown exactly as measured.

Task path / input to outcome

How to compress a PDF

01
Choose one PDF
Select Choose one PDF and open a document of up to 30 MB with at most 500 pages. The file opens inside this tab; nothing is uploaded.
02
Pick a compression mode
Choose Optimize structure or Strong compression under Compression mode. The workspace explains the trade next to each option, including what Strong compression costs.
03
Set the JPEG quality
For Strong compression, adjust JPEG quality between 0.3 and 0.9 — lower means a smaller file. Every page is re-rendered as a bitmap at 150 DPI, so text in the result can no longer be selected or searched.
04
Compress and compare
Press Compress PDF and check the before-and-after sizes with the exact reduction percentage. If the result is not smaller than the original, the tool says so plainly and still lets you download it.

Your input stays in the browser.

PDF Compressor uses its verified local execution path and does not create a hidden input or output history.

Local execution

Runs inside the current browser tab.

No hidden processing

Active tool data never becomes a Toolars document record.

No account required

Use the core workflow without creating a profile.

Immediate reset

Clear the tab and the active working data is gone.

When PDF Compressor is useful

Focused transformations

Complete one well-defined browser task without setting up another application.

Copy-ready output

Review the result beside its source before copying or downloading it.

Fast validation

Catch malformed input and stale results before they enter another workflow.

What PDF Compressor actually does

An application portal caps attachments at 5 MB and the scanned contract is 9; an image-heavy quarterly report takes forever to attach to email; an archive of old invoices needs to shrink before backup. PDF Compressor runs both of its honest modes in the browser, so the documents being squeezed — often the sensitive kind — never leave the device.

Deterministic output

The same source and selected mode produce the same result.

Source stays visible

Compare the original text and transformed value together.

Private by default

No active workspace value is stored or sent to a server.

Errors stay explicit

Invalid values return a clear error instead of stale output.

Common questions

What is the difference between the two modes?

Optimize structure removes the document metadata and rewrites the file structure; text stays selectable and searchable, but the reduction is usually limited because embedded images keep their original encoding. Strong compression re-renders every page as a 150 DPI JPEG at the quality you choose, which shrinks image-heavy files much further, at the cost of turning page text into bitmaps.

Why did Optimize structure barely shrink my file?

That mode does exactly two things — drop the info metadata and rewrite the structure — and both are honest but modest. If the PDF's size comes from embedded images, they keep their original encoding, so only Strong compression can reduce them. The before-and-after sizes are always shown exactly as measured.

What does the quality slider do?

It sets the JPEG quality for Strong compression between 0.3 and 0.9 (default 0.7). Lower values produce smaller files with more visible compression artifacts; every page is re-rendered at 150 DPI regardless of the setting.

Will I lose the ability to select and search text?

Only with Strong compression: its pages become bitmap images at 150 DPI, so text in the result can no longer be selected or searched — the workspace discloses this next to the controls before you run it. Optimize structure keeps text fully selectable and searchable.

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