Compress PDF online — beat Gmail 25 MB, IRS 5 MB and USCIS 25 MB caps

Drop your file, pick the Email preset, and download. The Email preset targets the 25 MB Gmail attachment cap (consumer Gmail and Google Workspace both). For Outlook.com / Microsoft 365 the cap is 20 MB and the preset stays under it on most documents; iCloud Mail caps at 20 MB too. PDFs heavy in scanned images (real-estate disclosures, IRS Form 1040 packets, USCIS Form I-130 evidence, medical records, contracts) shrink the most — typically 60–80% via JBIG2 (ISO/IEC 14492) on scanned text and JPEG2000 (ISO/IEC 15444) on color photos. Text-only legal briefs already optimized by Microsoft Word usually shrink 10–20%, since there is no image fat to cut — only Flate/Deflate (RFC 1951) recompression of the content stream and font subsetting.

For 1 MB use the Email preset on most documents — typical 5–10 MB scanned PDFs land at 800 KB–1.5 MB. For 500 KB / 200 KB / 100 KB targets, the math is unforgiving: a 20-page color-scanned PDF cannot reach 100 KB without going to grayscale at 72 DPI with JPEG quality 30 (text becomes blurry). Use Email preset first, then if you need to go lower, downgrade to grayscale and DPI 72. Smallpdf charges $9/mo Pro for the same control. Pi7, Zamzar and PDFgear all advertise compress to 1 MB with the same trade-off — they just hide it behind a vague slider.

Yes. No signup, no credit card, no 2-documents-per-day cap (the Smallpdf free-tier limit), no 3-tasks-per-hour cap (Sejda free), no Adobe ID required after 2 compressions (Adobe Acrobat online). Compress hundreds of files in a row if you need to. The whole tool runs in your browser via WebAssembly, so we have no server cost to ration. Adobe Acrobat Pro is $19.99/mo, Smallpdf Pro $9/mo, iLovePDF Premium $7/mo, Sejda Premium $7.50/mo, Foxit $9.99/mo, Soda PDF $7.99/mo, CloudConvert $9.99/mo, ILoveImg $4/mo.

No. iFillPDF compresses entirely client-side in your browser using WebAssembly + pdf-lib under ISO 32000-2:2020. Your file never leaves your device — not to us, not to AWS US-East-1, not to anyone. Competitors (iLovePDF, Smallpdf, PDF24, Adobe Acrobat online, Sejda, Foxit, Soda PDF, CloudConvert) all upload to their servers. Even when the page has loaded you can disconnect the network cable and keep compressing — the WebAssembly engine runs offline.

Yes. Only embedded raster images are downsampled and recompressed. The text layer (Tj/TJ content stream operators), embedded font subsets, hyperlinks (Annot Link), bookmarks (Outlines dictionary), AcroForm fields with their validation rules, page labels, ICC color profile and document metadata (Info + XMP) are preserved untouched. Ctrl+F still finds your terms in the compressed file. PAdES / PKCS#7 digital signatures stay valid where the compression keeps the signed byte ranges intact (most cheap compressors silently break signature integrity by re-encoding the page tree — we keep the original byte stream where possible).

Between 30% and 80%, depending on content. Image-heavy PDFs (scanned contracts, photo portfolios, real-estate disclosures, slide decks exported from PowerPoint) compress the most because JBIG2 on scanned bi-level text and JPEG2000 on color photos do most of the work. Pure-text PDFs already optimized by Microsoft Word or LaTeX may only shrink 10–20% — there is rarely much fat left to cut, only the content stream Flate level can be raised. Foxit, Smallpdf and Adobe Acrobat advertise up to 99% compression — that is only true on uncompressed scans straight from a Xerox / Brother MFP, never on a modern PDF.

It is GDPR-by-design, not just compliant. Because no personal data ever leaves your device (the compressor runs in your browser via WebAssembly), there is no data transfer to log under GDPR Art. 30, no processor agreement to sign under GDPR Art. 28, no Transfer Impact Assessment to file under GDPR Art. 46. Static assets and any optional account data sit in Frankfurt eu-central-1 (Hetzner Falkenstein, ISO 27001-aligned, TADPF) — outside the reach of the US Cloud Act and 50 USC §3024. HIPAA BAA available on the Unlimited plan for orgs that want a paper trail. Even EU-hosted competitors still process your file on their infrastructure — we do not process it at all. Material risk reduction for FRCP Rule 34 ESI productions, attorney-client privileged material, HIPAA PHI and trade secrets.

Around 200 MB on a modern laptop, limited only by your browser memory (Chrome / Edge / Safari WebAssembly heap). Smallpdf caps free users at 5 MB (Pro $9/mo to lift), iLovePDF at 25 MB (Premium $7/mo), Sejda at 50 MB and 200 pages free, Adobe Acrobat online at 100 MB, PDF24 at 100 MB. We cap at what your machine can hold — useful for SEC EDGAR 200 MB filings, ECF/PACER 35 MB per document caps, and discovery production batches.

Yes — once the iFillPDF page has loaded, you can disconnect from the internet and keep compressing. The WebAssembly engine runs entirely in your browser tab. Try that with iLovePDF, Smallpdf, PDF24, Adobe Acrobat online, Sejda, Foxit, Soda PDF or CloudConvert — all of them require a live connection to upload your file to their server.