CompressThis

Compress this.

PDF, image, video, Office doc — drop it, get back a smaller one. Free, no watermark, no signup.

Drop any file here

PDF · Image · Video · DOCX / PPTX / XLSX

or click to browseUp to 100 MB · 200 MB for video

Compression

Files are never stored. Processed in memory, sent straight back.

How it works

1

Drop your file

PDF, image, video, or Office document — drag it onto the page or click to browse. No signup needed.

2

Pick a compression level

Choose Good quality, Smaller, or Smallest. Or set an exact target size like 2 MB or 500 KB.

3

Download the smaller file

Your compressed file is ready in seconds. Download it, preview it, or email it directly.

Free file compression — no signup, no watermark

CompressThis is a free online tool that makes PDFs, images, videos, and Office documents smaller. It works entirely in your browser and on our servers — no software to install, no account to create, and no watermark on the output. Files are processed in memory and never stored.

For PDFs, CompressThis uses a two-pass approach: first it strips unused objects and recompresses streams (fast, lossless), then it resamples embedded images at a lower resolution if needed. For images, it re-encodes at optimized quality settings. For video, it uses FFmpeg with H.264 encoding. For Office documents (DOCX, PPTX, XLSX), it compresses the embedded images without touching text or formatting.

You can compress to three preset levels — Good quality, Smaller, or Smallest — or set an exact target size. Common targets include 2 MB for Common App uploads, 4 MB for USCIS, 25 MB for Gmail attachments, and 10 MB for LinkedIn.

Need to convert a file to PDF first? PDFThis converts images, Office documents, and web pages to PDF — then bring it here to compress.

Popular uses

Frequently asked questions

Is CompressThis free?

Yes. CompressThis is completely free with no file limits per day, no signup, and no watermark on the output. We support PDFs up to 100 MB and videos up to 200 MB.

Are my files stored on your servers?

No. Files are processed in memory and sent straight back to your browser. Nothing is stored, logged, or accessible after your session. Video files use temporary disk storage during FFmpeg processing and are deleted immediately after.

What file types can I compress?

PDF, JPEG, PNG, WebP, HEIC, GIF, MP4, MOV, AVI, MKV, WebM, DOCX, PPTX, and XLSX. If you need a format we don't support yet, drop it on the page and use the request form.

How much smaller will my file be?

It depends on the file. PDFs with large scanned images typically compress 50–80%. Phone videos compress 70–90%. Images compress 30–60%. Pre-optimized files may not compress further — the tool will tell you honestly.

Can I compress a file to a specific size?

Yes. Check 'Compress to a specific size' and either pick a preset (like Under 2 MB) or type any custom size. The tool will find the right compression level to hit your target.

Does compression reduce quality?

Slightly, depending on the mode. Good quality mode is nearly indistinguishable from the original. Smaller and Smallest modes reduce resolution and quality more aggressively. For PDFs, text is never affected — only embedded images are resampled.