FreeNo uploadNo sign-upBatch
Compress JPEG Images
Cut JPG file size for email, forms and websites. Choose the quality, see the savings instantly.
Drop JPG images to compress
batch and mixed formats welcome
- Private by design. Converted inside your browser.
- Instant. No upload queue, no waiting.
- Unlimited. Convert hundreds of files, download as ZIP.
How to compress JPEG images
Add your JPG images
Drop files on the tool, click Choose files or paste from the clipboard. Add as many as you like.
Set the quality
Move the quality slider. Lower means smaller files; the before and after sizes update instantly.
Download smaller files
Save each file or download everything as a ZIP. Files that cannot get smaller are returned unchanged.
Make JPGs small enough to send and upload
Phone and camera JPGs are often saved at very high quality, which makes them 3–10 MB each. Upload forms, marketplaces and email attachments rarely need that much.
Re-encoding a JPG at 75–85% quality typically removes half or more of the file size while the photo looks the same on screen. Everything happens on your device.
Frequently asked questions
What quality should I use to compress a JPG?
80–85% keeps photos visually identical in most cases. 60–70% gives much smaller files that are still fine for previews and listings.
Does this resize my photos?
No. The width and height stay the same; only the compression changes.
Why did my file not get smaller?
It was already compressed at a similar or lower quality. In that case the original is returned unchanged.
Can I compress many JPGs at once?
Yes. Drop as many files as you like and download them together as a ZIP.
Are my files uploaded to a server?
No. formatmath converts files with code that runs inside your browser. Your files are never uploaded, stored or seen by us.
Is it free?
Yes. There is no watermark and no daily limit. An account is optional and only keeps a history of your conversions.