Image Compressor Online
Compress JPG/PNG images in your browser with an adjustable quality slider.
Method and limitations reviewed August 3, 2026. Browser-first, no login required.
Your data is processed in your browser and not uploaded.
About this tool
What this tool does
The compressor redraws an uploaded image and exports a JPEG at the selected quality. It shows original and output sizes together so visual quality can be balanced against download size.
How the result is produced
- The browser decodes the source image and draws it at its original pixel dimensions on a canvas.
- Canvas export encodes the result as JPEG using the selected quality percentage.
- The reported saving compares the generated Blob size with the original file size.
- A fresh preview is generated whenever the quality slider changes.
Good uses
- Reducing photographs before web upload
- Comparing JPEG quality levels visually
- Preparing smaller email or form attachments
How to verify the result
- Inspect faces, text, gradients and sharp edges at full size.
- Confirm the new file is actually smaller; some already-optimized sources may grow.
- Keep the original when transparency or metadata matters.
Known limitations
- Output is always JPEG, so transparent areas are flattened by the browser.
- Compression is lossy and repeated re-encoding can create visible artifacts.
- Metadata such as EXIF may not be retained in the canvas export.