How it works
Your browser decodes each image, optionally scales it down, and encodes it again as JPG or WebP at the quality you choose. In target-size mode it searches for the highest quality that fits under your limit, and only shrinks the image if even a low quality is too large. Nothing is uploaded.
photo.jpg 4.8 MB (4000×3000) → 1920 px, quality 75% → about 450 KB
Which setting to use
- Quality 70–80%: the best balance for photos on websites, email and messengers.
- Target size: when a form or site sets a limit, such as 200 KB or 1 MB.
- Best for each file: JPG stays JPG; PNG and WebP become WebP, which keeps transparency and is much smaller than PNG.
Tips
- Reducing the longest side to 1920 px usually cuts a phone photo by 70–90%.
- Screenshots and logos saved as PNG shrink the most when converted to WebP.
- Location and camera data (EXIF) are not copied into the compressed file.
- Very large batches can be slow on phones; compress 10–20 at a time.
Standards and sources
- HTML Standard — canvas toBlob() image encoding · WHATWG
- ITU-T T.81 — JPEG still image compression · ITU
- RFC 9649 — WebP image format · IETF
Last reviewed October 15, 2026
Frequently asked questions
Are my images uploaded?
No. Compression runs in your browser, so the files never leave your device.
How do I get a photo under 200 KB?
Choose Target size and enter 200. The tool lowers the quality until the file fits and only shrinks the image if it has to.
Why didn't my file get smaller?
It was already well compressed. When the new file would be larger, the original is kept.
Will a transparent PNG stay transparent?
Yes with Best for each file or WebP. JPG has no transparency, so transparent areas turn white.
Is EXIF data removed?
Yes. The compressed file is encoded fresh, so location and camera data are not included.