For a photograph that is larger than you need, start by reducing its pixel dimensions and then export a compressed copy. ShamsMag's image compressor processes the selected file in your browser; the tool code does not send the image to a server.
Keep the original
Make a copy before changing an important image. A smaller web version is useful for a page or newsletter, while the original may still be needed for printing, cropping or later edits. Use a filename that distinguishes the exported copy from the source.
Choose dimensions for the actual placement
A full-width feature image and a small article thumbnail do not need the same dimensions. Check where the image will appear, then choose a maximum width that provides enough detail for that placement. Enlarging a small source will not recover detail that was never present.
Use the ShamsMag compressor
- Open the image compressor.
- Select a JPEG, PNG or WebP file under 20 MB.
- Set the maximum width. The tool keeps the aspect ratio and does not upscale a smaller image.
- Choose a quality setting and select Compress image.
- Read the output dimensions and file size, then download the WebP copy.
The tool limits output width to 4,000 pixels and rejects exceptionally large decoded dimensions. These are practical limits of this implementation, not universal limits of the image formats.
Inspect the exported copy
Open the downloaded file at the size your readers will use. Check fine text, faces, gradients and sharp edges. If artifacts are distracting, increase quality or keep a larger export. If a photograph contains text that readers need to read, consider placing that text in the page itself as well.
Compare bytes, not just the file extension. A source image may already be efficiently compressed, so another conversion does not always produce a smaller file. Keep the version that meets your visual requirements without unnecessary size.
Know what this tool changes
This workflow exports a still image. It is not designed to preserve animation, editing layers or an original file's complete metadata. Browser image decoding and encoding can also affect how a result appears. For color-critical work, review the export in the intended workflow before publishing.
Accessibility still matters
A compressed image needs a useful description when its content matters to the page. Describe the information a reader would miss, rather than filling the description with keywords. If the image is purely decorative, an empty alternative description can be appropriate.
Technical reference
The tool draws the chosen image into a browser canvas and exports the result. MDN's Canvas image tutorial explains the drawing and scaling operations behind this approach. The instructions and implementation limits above describe ShamsMag's own tool.