Resize images for the web without uploading

Web pages do not need your 12 MP original. Serving a 3600-pixel JPEG into a 720-pixel column wastes bandwidth and slows Largest Contentful Paint. web.dev on responsive images is still the right mental model: ship the pixels the layout will actually show.

Pick a target, not a vibe

• Blog hero: 1920 px on the long edge is plenty for most themes.
• Inline figure: 1200 px wide, then let CSS scale down.
• Avatar or logo: the displayed size times 2, for 2× screens.
• Marketplace listing: follow the host’s documented pixel box, then compress.

How StackImage resizes

You can lock a width, a height, or a long edge, and keep aspect ratio. The browser draws the bitmap into a smaller canvas and encodes the result. That is a high-quality downsample for everyday photos. It is not Lightroom’s proprietary sharpening pipeline. Images above 32 megapixels or 50 MB are rejected so the tab stays up.

1. Open Resize Image and drop the file.
2. Enter the width, height, or long-edge target.
3. Preview, then download. Run Compress afterward if the encode is still heavy.

Resize is not crop, and it is not upscale

Crop changes the framing. Resize changes the pixel grid. Upscale invents pixels with a model and is a different tool: typical phone photos run at 2×, and larger frames are fitted first. If you need a 1:1 Instagram square, crop first, then resize to 1080.

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