Product images do double duty in an online store: they sell (zoomable detail, accurate color, lifestyle context) and they cost (bytes on every category page). Slow category pages suppress conversion and rankings; blurry product photos suppress sales. The optimization job is finding the size where images are still persuasive but the pages stay fast.
Batch your product shots: the compressor handles multiple files at once with a uniform target — consistent library, one pass.
Compress product imagesTargets that work
| Image | Dimensions (square) | File size target |
|---|---|---|
| Product main image | 1600–2048 px | 150–300 KB (WebP) |
| Gallery thumbnails | 400–600 px | 30–60 KB |
| Category grid tiles | 600–800 px | 60–100 KB |
| Lifestyle / hero banner | 2880 px wide | 250–400 KB |
Rationale: 2048 px square covers marketplace zoom requirements (Amazon recommends ≥1600 px for zoom) and Shopify's retina-grade display, while 300 KB in WebP keeps even a 24-tile category page under ~2.5 MB of images.
One master image, correct derivations
Keep a single high-quality master per product (full resolution, untouched). Generate every storefront size from that master — never scale up a thumbnail, never screenshot the webpage version for a marketplace listing. Platforms regenerate their own sizes from what you upload; giving them a clean, well-compressed master is what keeps every derivative decent.
Marketplace-specific notes
- Amazon: JPEG preferred (WebP accepted), product images 1600 px+ for zoom, pure white background for the main image. File size cap is generous — the zoom resolution matters more than aggressive compression.
- eBay: JPEG/PNG, minimum 500 px on the longest side, 500 px+ recommended for zoom; keep listings well under the 7 MB per-image cap because pages show many images at once.
- Etsy: 2000 px+ recommended, JPEG for photos. Listing thumbnails are heavy — compress gallery images so a 10-photo listing doesn't weigh 20 MB.
- Shopify / WooCommerce / custom stores: WebP everywhere, lazy-loaded galleries, explicit width/height to prevent layout shift.
Photography habits that make compression easier
Compression quality starts at capture. Even, neutral lighting produces images with less noise — and noise is exactly what lossy codecs spend their bytes on. Clean backgrounds, stable exposures and consistent framing across a product set also mean one uniform target size works for the whole batch, instead of tuning each file separately.
The batch workflow
- Shoot against a consistent background; keep a RAW or high-quality original of everything.
- Batch-crop to square, export masters at 2048 px.
- Drop the batch into the JpegDiet compressor — target 200 KB, WebP output.
- Upload compressed versions to your store and marketplaces.
- Check one product page in PageSpeed Insights; adjust the target if the image weight dominates.