Our take: It shows the estimated result size before you compress, which makes choosing easy. We got −99% without signing up; files are deleted after 1 hour. Stronger levels and repeated use push you toward a paid trial.
- ✓ One task without sign-up — tested
- ✓ PDF −99% — tested
- Estimated size preview · deleted after 1 hour
- ! Uploads to server — tested
- ? China access — not tested yet
Our test
Tested 28 Sep 2026 · Chrome desktop · synthetic 3-page test PDF with one embedded photo, 3.89 MB (same file for all four tools)
How we checked privacy: The PDF was uploaded to Smallpdf’s file servers (files.smallpdf.com, Cloudflare storage) and processed by its task server. Smallpdf says files processed with its free tools are deleted after 1 hour.
Data sheet
Every row shows how we know it
| Free limit | One compress + download without an account · repeat use pushes Pro Tested |
|---|---|
| Sign-up | Not required (one task) Tested |
| Watermark | None Tested |
| Levels | Basic → Smallest · Custom (some paid) Tested |
| File processing | Uploaded to Smallpdf servers Tested |
| File retention | Free-tool files deleted after 1 hour Official |
| Upsell | Free Trial / Pro prompts Tested |
| Access from China | — Not tested |
When to use it
When you want to see how many KB you’ll get before choosing a level.
Before you use it
Files are uploaded. Stronger levels and frequent use lead to a paid trial — if you compress often, compare iLovePDF or Sejda.
How to use it
- Open Smallpdf’s Compress PDF page.
- Upload the PDF and choose a level using the size estimate.
- Press Compress, then Download.
Alternatives
Guide: How to merge PDFs: compare free tools and upload requirements
Last verified 28 Sep 2026 · Found something outdated? Tell us. · Official security article