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アップロード、マーク、送信。数分で文書に署名を。

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Free PDF Compressor

Shrink a PDF's file size without flattening it to an image — your text stays selectable and searchable. Free, and everything happens in your browser.

ここにPDFをドロップしてアップロード

PDFファイル、最大50MB — すべてブラウザ内で処理されます

Frequently asked questions

Yes, completely free with no account or sign-up required, and no limit on how many files you compress.

No. Compression happens entirely in your browser — your file is never sent anywhere.

It finds the photos and scanned pages embedded in your PDF and re-compresses just those images at a lower quality — the same kind of size/quality trade-off as saving a JPEG at 60% instead of 100%. Everything else in the document (text, fonts, layout) is left completely alone.

Yes — this is the main thing that sets this tool apart from a lot of free "compress PDF" tools, which flatten every page into an image and quietly make your text impossible to select, search, or copy. This tool never touches the text layer, only the embedded images.

This works by recompressing embedded photos and scans, so a PDF that's mostly text with few or no images won't shrink much — there's little to compress. It also only processes images already saved as JPEG (the most common case for photos and scans); other image formats are left as-is rather than risk damaging them.

This page just shrinks a PDF's file size for you to download. SignFastAi's core product lets you upload a document, place signature fields on it, and send a secure signing link to get it signed.

Need to get this PDF signed instead?

SignFastAi lets you upload a document, mark where to sign, and send a secure link — no enterprise contract or sales call required.

Get started free