Are my images uploaded?

No. Compression happens in your browser.

Why is the file sometimes bigger?

Re-encoding an already compressed image at high quality can add bytes. Lower the quality or keep the original.

JPEG for photos, WebP for the smallest files when your platform supports it.

Shrink a photo before emailing, uploading or sending it on WhatsApp.

Images never leave your device.

Choose an image

Quality

Between 5 and 100.

Output format

Choose an image to compress.

The image is drawn onto a canvas and re-encoded at the quality you choose. Lower quality means a smaller file with more visible artefacts.

Are my images uploaded?: No. Compression happens in your browser.
Why is the file sometimes bigger?: Re-encoding an already compressed image at high quality can add bytes. Lower the quality or keep the original.
Which format should I choose?: JPEG for photos, WebP for the smallest files when your platform supports it.