Compress PDF

A scanned lease agreement comes in at 18MB. Your property management portal caps uploads at 5MB. You either pay for Adobe Acrobat at $19.99/month, or you use PDFKits to compress the file in your browser — free, in about ten seconds.

PDF compression matters in three recurring situations: emailing attachments that hit spam or size filters (Gmail caps individual attachments at 25MB), uploading to portals with strict limits (government forms typically allow 2–10MB), and freeing storage space on shared drives. PDFKits lets you pick from multiple compression levels depending on whether you prioritize file size or image sharpness. The file is compressed entirely on your device — nothing is sent to a server, so confidential documents stay private throughout.

How It Works

Step 1 — Upload your PDF

Drag your PDF into the tool or click to select it. The file is loaded into browser memory immediately. You will see the original file size displayed in the interface — this gives you a baseline before choosing how aggressively to compress. A 30-page report with photos might show 22MB; a text-only legal brief might show 800KB already.

Step 2 — Choose a compression level

PDFKits offers three levels. Light compression reduces image resolution slightly and removes redundant internal data — typical reduction of 20–40%, minimal visible quality change. Medium compression targets 40–60% reduction; images stay readable but lose fine detail. Strong compression maximises size reduction at 60–80%; good for archiving documents where print quality is not critical. For a scanned photo-heavy lease, strong compression often brings an 18MB file to under 4MB — small enough for any portal.

Step 3 — Compress and download

Click Compress. Processing happens locally in your browser using JavaScript. A 20MB document at medium compression typically finishes in 5–15 seconds. The tool shows the output file size and the percentage reduction before you download. If the result is still too large, switch to a stronger setting and run again — there is no daily limit. The compressed PDF downloads directly to your device; your original file is untouched.

Use Cases

Job applications

Applicant tracking systems at large companies often cap résumé uploads at 2MB or 5MB. A portfolio PDF with project screenshots can easily exceed that. A graphic designer compresses her 14MB portfolio to 1.8MB without any visible degradation, uploads successfully, and does not miss the deadline.

Government and tax filings

Many government portals — from visa applications to tax authority submissions — require PDFs under 5MB. An accountant handling 40 client tax returns, each with scanned receipts, uses PDFKits to compress each file before uploading to the national tax portal.

Email attachments

Corporate email servers often reject attachments above 10MB. A project manager sending a 17MB architecture report to a client compresses it to 4.2MB with medium compression, keeping charts readable while fitting comfortably under any email size limit.

Cloud storage and shared drives

A small legal firm stores case files in shared Google Drive folders approaching storage limits. Compressing 200 archived PDFs saves several gigabytes without affecting day-to-day readability.

Medical records

Scanned medical forms and lab results can run 5–15MB per document. A clinic administrator compresses patient intake forms before adding them to the electronic health record system, keeping storage costs manageable.

PDFKits vs. Alternatives

Adobe Acrobat Pro charges $29.99/month and is the benchmark for PDF compression quality. Smallpdf and iLovePDF free plans limit you to two compressions per day and upload files to remote servers. PDFKits compresses unlimited files, locally, at no cost.

FeaturePDFKitsSmallpdfiLovePDFAdobe Acrobat Pro
CostFree, always2 tasks/day free2 tasks/day free$29.99/month
Files stay on your deviceYesNo — cloudNo — cloudNo — cloud
Multiple compression levelsYesYesYesYes
Watermark on outputNoneAdded on free planAdded on free planNone
Daily limitUnlimited2/day2/dayUnlimited

For accountants, HR teams, or anyone compressing dozens of files per day, the daily cap on competitor free plans is a real obstacle. PDFKits removes that friction entirely.

Frequently Asked Questions

How much can I reduce a PDF file size?

Results vary by content. Image-heavy PDFs (scans, portfolios) typically reduce by 50–80%. Text-only PDFs may only shrink 10–30% since text compresses efficiently by default.

Is the compression free forever?

Yes. PDFKits has no daily task limit, no file size cap, and no subscription. You can compress as many files as you need without creating an account.

Are my files uploaded to your server?

No. Compression runs entirely in your browser via JavaScript. Your PDF never leaves your device and is never transmitted to PDFKits or any third party.

Does compression reduce text quality?

No. PDF text is stored as vector data and is not affected by image compression settings. Only embedded images are reduced in resolution.

What is the maximum file size?

There is no enforced limit. Practical limits depend on your device's available memory. Files up to 200–300MB compress reliably on most modern computers.

Does it work on mobile (iPhone, Android)?

Yes. Open pdfkits.app in any mobile browser. Processing is slightly slower on phones due to less RAM, but most documents compress without issues.

Can I compress a password-protected PDF?

No. Locked PDFs cannot be processed. Use PDFKits Unlock PDF to remove the password first, then compress the file.

What if the compressed file is still too large?

Switch to a stronger compression level and run again. If the PDF contains high-resolution scans, strong compression will produce the largest reduction.

Will compression affect the PDF's searchability?

No. Searchable text layers and embedded fonts are not touched by compression. Only image data is affected.

Is my compressed PDF GDPR compliant to share?

PDFKits does not process or store your file, so no GDPR obligation arises from using the tool. The compressed output is identical in content to the original.