Compress PDF
Reduce PDF file size by up to 90%, or compress a PDF to any exact size you specify — free, fast, no signup.
Need a smaller PDF to attach to an email, upload to a portal, or share on a website? mydearPDF gives you two powerful ways to compress your PDF. Choose a quality level (Low, Medium, or High) for a quick reduction, or switch to "By Size" and type the exact kilobyte target you need — 47 KB, 150 KB, 350 KB, or anything in between. Our iterative multi-engine pipeline (Ghostscript, qpdf, pdfcpu, and Sharp) keeps compressing until your PDF fits under the target size while retaining legibility. Most PDFs shrink by 30–90%. No watermark, no signup, no hidden limits.
Secure
HTTPS transport. Files removed after processing.
High quality
Resilient open-source engine pipeline.
Fast & easy
Drop, process, download — in seconds.
How to compress pdf with mydearPDF
- 1
Upload your PDF
Click the upload area or drag and drop a single PDF file. mydearPDF supports files up to 100 MB.
- 2
Choose your compression mode
Select "By Quality" for Low, Medium, or High compression, or switch to "By Size" to set an exact target. Click one of the preset sizes (20, 30, 50, 100, 200, 300, 500 KB) or type any custom value in the input field.
- 3
Click Compress PDF
Hit the Compress PDF button. The server analyses your document and runs the optimal engine pipeline to hit your target.
- 4
Download your compressed PDF
See the before/after size stats, then click Download to save mydearpdf-compress.pdf to your device.
Built for speed, privacy, and zero friction
- Compress to any exact size — type 47 KB, 150 KB, or any custom target
- Preset quick-picks: 20, 30, 50, 100, 200, 300, 500 KB in one click
- Three quality levels — Low, Medium, High — for level-based compression
- Multi-engine pipeline picks the best compressor for your file
- See real before/after stats and reduction percentage
- No watermark, no signup, no daily limits
Frequently asked questions
Can I compress a PDF to an exact file size like 100 KB or 200 KB?
Yes. Switch to the "By Size" mode and either click a preset (20, 30, 50, 100, 200, 300, 500 KB) or type any custom target into the input field. mydearPDF runs an iterative compression pipeline to get as close as possible to your target without making the document unreadable.
How much can I compress a PDF?
Compression depends on the content. Text-only PDFs typically shrink by 10–30%, mixed PDFs by 30–60%, and image-heavy or scanned PDFs can shrink by 70–90%. For a specific target size, the iterative pipeline keeps compressing until it hits your limit or reaches the minimum possible size.
What if my PDF cannot reach the target size I set?
If your PDF is already smaller than the target, it is returned as-is. If the target is too aggressive for the content (e.g. compressing a 5 MB scan to 10 KB), we deliver the smallest achievable size and show you the result in the stats panel so you can decide whether to try a lower target.
Does compression reduce the quality of my PDF?
On Low level or with a generous target size, quality is virtually unchanged. Medium and High levels — or aggressive size targets — recompress embedded images. At most quality levels, the difference is imperceptible. If quality is critical, use Low or set a generous target size.
Why is my PDF not getting smaller?
Some PDFs are already fully optimized (e.g., exported from recent versions of Word or Adobe). If our pipeline detects that compression would make the file larger, we return the original automatically — you will never receive a bigger file than you uploaded.
Is there a file size limit?
The maximum upload size is 100 MB per file. This covers nearly every real-world PDF, including most scanned documents and image-rich reports.
Are my files private when I compress them online?
Yes. Files are uploaded over HTTPS, processed in isolated memory or a temporary directory, and deleted from our server immediately after the compressed file is delivered to you.
Most online PDF compressors give you one or two compression settings and little else. mydearPDF goes further: you can compress by quality level (Low for the best visual fidelity, Medium for a balanced tradeoff, High for the smallest possible file), or you can switch to target-size mode and type the exact kilobyte limit you need — whether that is 47 KB for a strict government portal upload, 200 KB for an email attachment limit, or any other number. The iterative multi-engine pipeline — powered by Ghostscript, qpdf, pdfcpu, and Sharp — keeps compressing in rounds until your PDF fits under the target while remaining legible. Real-time stats show you the original size, compressed size, percentage saved, processing time, and which engines were used, so you always know exactly what happened. If the compressed output is larger than the original (unusual, but possible with already-optimized files), we revert automatically — you never get a worse file than you started with.