How can I verify the image isn't uploaded?

Open your browser's DevTools (F12) and go to the Network tab. Compress an image while watching for requests. No outbound connections appear because all processing happens locally in your browser tab using the Canvas API.

Why compress images without uploading?

Some files are not appropriate to send to a third-party service, and some networks block uploads altogether. Processing locally avoids both problems.

Which image formats are supported?

JPEG, PNG, and WebP are supported as inputs. Choose JPG, PNG, or WebP as the output format in the tool.

How much can I reduce an image's file size?

File size reduction depends on the original image and the quality setting you choose. A typical photograph can be reduced by 40–80% while remaining clearly legible.

Compress Image Without Uploading

Reduce your image file size entirely in your browser. Our servers are not involved at any point. Drag and drop your image, adjust the quality slider, click Compress, and download the compressed result.

Drop an image or click to choose

JPG, PNG, or WebP, up to 50 MB. Runs in your browser.

FORMAT

QUALITY 80%

Runs entirely in your browser

How it works

Dropping an image triggers the Canvas API to decode the pixels in memory, inside this tab. Set the quality and format, then click Compress: ctx.canvas.toBlob() re-encodes the image so you can compare the size and the preview before downloading. Change the quality and click Compress again to try another setting. Everything from decoding to encoding to the final download happens inside this browser tab.

Processing runs in your browser

Open DevTools to the Network tab, drop an image, set the quality and click Compress, and you will see zero outbound requests. The Canvas API encodes locally. You can confirm this yourself in your browser's DevTools Network tab.

Related operations

If you need a different file format after compressing, try the image converter. To trim images to a specific aspect ratio first, use image crop. For multi-image PDFs from compressed photos, see image to PDF.

Frequently asked questions

How can I verify the image isn't uploaded?: Open your browser's DevTools (F12) and go to the Network tab. Compress an image while watching for requests. No outbound connections appear because all processing happens locally in your browser tab using the Canvas API.
Why compress images without uploading?: Some files are not appropriate to send to a third-party service, and some networks block uploads altogether. Processing locally avoids both problems.
Which image formats are supported?: JPEG, PNG, and WebP are supported as inputs. Choose JPG, PNG, or WebP as the output format in the tool.
How much can I reduce an image's file size?: File size reduction depends on the original image and the quality setting you choose. A typical photograph can be reduced by 40–80% while remaining clearly legible.

Last reviewed September 30, 2026

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