Shrink PDFs to under 500KB for email and uploads — free, no sign-up, your file never leaves the browser.
Why is my PDF so large?
Most oversized PDFs are full of high-resolution images — scans or phone photos saved at print quality. Embedded fonts, duplicated resources and hidden metadata add extra weight on top.
ShrinkPDF downsamples those embedded images to a screen-friendly resolution and re-encodes them, iterating until the file fits your target size. Text and vector graphics are never touched, so documents stay sharp while the images shrink.
Unlike typical online compressors, everything happens locally with JavaScript: your PDF is never uploaded to a server. That makes this the safe choice for contracts, visa documents and anything confidential.
When you need a 500KB PDF
500KB is the sweet spot for everyday sharing:
- Email attachments — strict corporate mail servers and older providers bounce oversized files.
- LMS assignment uploads — Moodle, Canvas and Google Classroom submissions with tight caps.
- Insurance claims — supporting documents that must stay small.
At 500KB, photos stay crisp while the file sails through any limit.
Frequently asked questions
Will my file be uploaded to a server?
No. The entire compression runs in your browser using JavaScript. Your PDF never leaves your device — open DevTools → Network tab while compressing and you will see zero upload requests.
What if my PDF can't be compressed to 500KB?
You will still get the smallest version we could produce, with a clear notice that the target wasn't reached. This usually happens with very dense black-and-white scans or vector-heavy presentations. Splitting the file and compressing the parts separately usually helps.
Does compression affect text sharpness?
No. Compression only re-encodes the embedded images; text and vector graphics are never resampled, so they stay perfectly sharp.
What is the maximum file size?
50 MB per file. Larger files should be split first, then each part compressed.
Does it work on mobile?
Yes — it works in the browsers on iPhone, Android, Windows and Mac. No app to install.
Is there a daily limit? Is it really free?
No limits, no account, no watermark. Free forever for the core compression.
How is this different from iLovePDF or Smallpdf?
Those services upload your file to their servers for processing. ShrinkPDF compresses locally in your browser, so sensitive documents never leave your machine — and you can verify it yourself in the Network tab.