JW Tool Box

Image Resizer: Resize JPG, PNG, and WebP

Perfect for blog thumbnails, app icons, and social images—resize and convert locally with one click.

Resize images to exact dimensions and convert to WebP, JPEG, or PNG entirely in your browser.

Resize an image to a maximum width and height, preserve its aspect ratio, and export WebP, JPEG, or PNG. Preview the output dimensions and file size before downloading. Your image is processed in this browser.

How this page is maintained

  • Steps and copy are checked against the current tool behavior.
  • Browser limits, file-size constraints, or compatibility gaps are documented when relevant.
  • Unless a page explicitly says otherwise, files and text stay in the browser during processing.

Resize an Image to a Width and Height

Select an image, then enter Max width and Max height in pixels. With Keep aspect ratio selected, the image fits inside those limits without stretching. For example, a 2400 × 1600 photo fitted into 1200 × 1200 becomes 1200 × 800.

Exact Dimensions or a Proportional Fit?

Keep aspect ratio enabled for photographs and artwork. This mode reduces larger images and does not enlarge smaller ones. Turning it off uses the requested width and height directly, which can stretch the picture. To make a square or portrait image without stretching, use the image cropper first.

Choose WebP, JPEG, or PNG

WebP is the default output. JPEG is useful for photos where transparency is not needed. PNG supports transparency and has no quality slider. JPEG and WebP use the quality control; a lower value may reduce file size but can introduce visible artifacts. The result depends on the source image.

Preview Before Downloading

Click Resize & convert, compare the original and result previews, and check the displayed dimensions, format, and file size. Download the result when it matches your needs. Browser canvas output may not retain the source file's metadata or color profile, so keep your original file for future edits.

Dimensions and File-Size Limits Are Different

A form asking for 1200 × 800 pixels requires dimensions; a form asking for less than 200 KB requires a file-size limit. Resizing can help reduce bytes, but does not guarantee a particular limit. Use the image compressor when you need to target a file size.

Prepare Images for a Specific Use

For social posts, check the image sizing guide before choosing dimensions. For a website, choose dimensions close to the displayed size rather than exporting the largest version. The image stays in this browser and is not uploaded to JW Tool Box.

Key features

  • Fit to size safely: Set max width and height, keep aspect ratio, and preview before exporting to avoid stretched images.
  • Flexible formats: Export to WebP for smaller files or keep JPEG/PNG when you need compatibility or lossless output.
  • Browser-only workflow: Images are processed with canvas in your browser and are not uploaded to JW Tool Box. The site separately collects usage information as described in the Privacy Policy.

Frequently asked questions

Is this tool free to use?

Yes. This tool is free to use without an account or sign-up.

Will the aspect ratio be preserved?

By default yes—set max width/height and the tool fits inside that box. You can turn off aspect lock if you need exact dimensions.

Do my images get uploaded?

Resizing and format conversion happen locally using the canvas API; image files are not uploaded to JW Tool Box. The site separately collects usage information as described in the Privacy Policy.

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