Shopify guide
How to reduce Shopify image size without losing quality
You can shrink product photos a lot before anyone notices. Shoppers notice a 6-second product page. They do not notice 85 vs 92 JPEG quality on a phone.
Do this in your editor first
Resize to the largest size the theme actually displays (often 2000px or less). Strip EXIF if you do not need GPS. Export JPEG quality 75–85 for lifestyle photos; go higher only for jewelry or fabric close-ups.
What Shopify already does
Shopify’s CDN resizes and can serve modern formats to supporting browsers. It still has to download your original into the files API. Huge originals cost you admin uploads, backups, and first-byte work on new transforms.
Apps vs theme
A speed app that lazy-loads can hide the problem on the homepage and still leave product zoom pulling a giant file. Compression plus sane dimensions is the real fix. Then remove unused image-heavy apps.
Use Seoi, or send the store for a check
Seoi compresses catalog images as part of SEO Image Optimiser so you are not exporting 2,000 files by hand. Pair it with a theme pass if apps are the other half of the weight.