Compress a PDF online free
Images inside the document get recompressed — a much lighter file with crisp text.
Less weight — same readability
How to compress a PDF in 4 steps
Up to 25 MB.
The processor recompresses raster images inside.
Scans and decks slim down 2–10×.
Already optimal? We return the original.
Part of the Zerocoder platform
One tool of a platform where AI generates websites, images, video, text and documents — under one subscription.
A heavy PDF is the eternal obstacle: email caps attachments at 10–25 MB, upload forms are stricter. Nearly all the weight is raster images inside; compression brings them to a sensible resolution without touching text or vector graphics. Processed on our servers, never stored. Need only some pages — extract them first; joining documents is merge. The rest of the tools — in one section.
Why PDFs get so heavy
Scans at 300–600 dpi, phone photos, uncompressed decks — they sit inside the document as-is. Screen reading needs half or a third of that resolution — which is exactly what compression exploits: images shrink, structure and text stay.
Compression for email and portals
The rule of thumb: under 10 MB passes almost everywhere. A 40 MB contract scan usually lands at 4–8 MB. Still too big — split the document with page extraction and send in two parts.
When compression won't help
A text-only PDF is already small — nothing to squeeze, you get the original back. Free an encrypted file from its password first. And if you need one page as an image, PDF to JPG is faster.
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FAQ
How much smaller will it get?
Scans and decks — 2–10×; text-only PDFs barely shrink, they have nothing to lose.
Will text stay sharp?
Yes: only raster images are recompressed; text and vectors are untouched.
What if the file didn't shrink?
It was already optimal — we return the original unchanged, never worse.
Good enough for official filings?
Yes, document structure is preserved; signature images stay in place.
What's the size limit?
Up to 25 MB in.
Do I need an account?
Your first result needs no account. After that we ask for a free sign-up: signed-in users get 5 runs per day, and the Zerocoder Studio has no limits.
What happens to my files?
Nothing is stored: processing uses memory and temp files that are deleted immediately.
Does a password block it?
Yes, encrypted files aren't processed — remove protection first.
What else does Zerocoder do?
AI document, text and image generation, courses, jobs — the PDF utilities are one part of the Studio.