Image Size Checker Pro

Check image size and compress images for page speed. Shows measured savings. Files keep the same name, format and dimensions.

Heavy images are the most common reason a page loads slowly. Image Size Checker Pro shows you which images are too big, by how much, and fixes them without changing your markup. AUDIT ANY PAGE • File size, pixel dimensions and how each image is actually displayed • Flags images over your size limit, images with far more pixels than they need, stretched or squashed images, and missing alt text • Achievable savings are measured by really compressing each image, not guessed • Badges and tooltips right on the page, or a clean report in the popup or side panel COMPRESS AS DROP-IN REPLACEMENTS • Same filename, same format, same pixel dimensions, so you can overwrite the original files • PNG compression is lossless and pixel-exact • JPEG and WebP keep high quality by default; preview before and after and pick the quality yourself • Compress one image, or everything at once into a ZIP • Save straight into a folder you choose (for example your site's images folder) or use the Save-As dialog RESIZE FOR HOW IMAGES ARE DISPLAYED • Creates 1x and 2x versions sized for the space each image fills, never upscaled • Gives you ready-to-paste srcset markup OPTIONAL EXTRAS • WebP copies with <picture> markup • Lossy PNG (256-color palette), used only when the result is visually near-identical • Export the audit as CSV, JSON or a Markdown table PRIVATE BY DESIGN No accounts, no analytics, no tracking. Pages are scanned only when you ask (unless you turn on auto-scan), all processing happens in your browser, and files are saved only to your computer. Optional keyboard shortcuts: pick your own keys to open the extension or show and hide the on-page badges.