How to Compress a PDF Without Destroying Its Quality
Shrink oversized PDFs to pass email limits and upload caps — re-save structure or rasterize pages to JPEG, privately in your browser.
"Attachment exceeds the maximum size." Every PDF compression journey starts with that message. A scanned contract that should be a couple of megabytes somehow weighs 40 MB, the portal rejects it, and you need it smaller now — without turning the text into mush.
Skip the theory — use the free Compress PDF tool
Why PDFs get so heavy
Almost always: images. A PDF made from scans or phone photos stores each page as a large picture, often at far higher resolution than any screen or printer will ever show. Text-based PDFs (exported from Word, for instance) are usually small already — if yours isn't, embedded images or fonts are the likely culprits.
Understanding this explains the two strategies in the tool:
Re-save & tidy structure rewrites the PDF without changing page content. Text stays selectable; size may shrink slightly or occasionally grow. Use it when you must keep selectable text.
Strong (rasterize) draws each page as a JPEG at a chosen size/quality (optional grayscale). Scans and image-heavy PDFs often shrink a lot; text is no longer selectable. A quick estimate warns before processing if the result would grow.
Compressing step by step
- Open the Compress PDF tool and drop your file in.
- Choose Re-save & tidy (keep text) or Strong (rasterize), and for Strong pick size/quality and optional grayscale.
- Compress, check the before/after size, and download.
If the result is still too large, run strong compression; if it's a scan, that's where the big wins live.
Practical tips
Compress after merging, not before. Combining files first and compressing once gives better results than compressing pieces individually.
Keep an original. Compression can't be reversed — the discarded image data is gone. Archive the full-quality original and share the compressed copy.
Sign first, compress second if a workflow requires both, so your signature is part of the final optimized file.
The privacy angle
The documents people compress are usually the sensitive ones — contracts, applications, financial statements. On Kitzos, compression runs entirely on your device: the file is never uploaded, processed remotely, or "stored for 2 hours" on anyone's server.
Common questions
How much smaller will my file get? Scans: often 70–90% smaller with strong compression. Already-optimized text PDFs: sometimes only a few percent — there's simply little to remove.
Will text stay sharp? Re-save keeps real selectable text untouched. Strong turns pages into images, so “text” sharpness follows JPEG settings — prefer Re-save when selectable text must stay perfect.
Is there a size limit? No imposed limit; your device's memory is the only bound.
Open the free Compress PDF tool and get that attachment under the limit.
Use the free Compress PDF tool