Compression should make files smaller, not ruin them. When an image looks blurry after export, the cause is usually one of three things: the dimensions were reduced too far, the quality setting was too low, or the format does not match the content.

Photos, screenshots and logos fail in different ways. Photos show blocky artifacts and smeared texture. Screenshots show fuzzy text. Logos show jagged edges or color halos. Fixing the problem starts with identifying which kind of image you are working with.

If an image will appear 1000 pixels wide on a page, exporting it at 600 pixels wide forces the browser or app to upscale it. Upscaling makes the image soft even if compression quality is high. Always export at least the display size, and often a bit larger for high-DPI screens.

For thumbnails, smaller dimensions are fine because the image appears small. For hero images, product photos and tutorial screenshots, being too small is much more visible.

Use JPG or WebP for photos and PNG for screenshots, icons and graphics with text. If you must use JPG for a screenshot, keep quality high and check the text carefully. Low-quality JPG is especially bad for flat colors and letters.

Export a few versions and compare them at final size. The smallest acceptable file is the goal, not the smallest possible file. If the image supports a sale, instruction or important message, clarity is worth a few extra kilobytes.