Every marketplace asks for large images so buyers can zoom in, then caps how heavy a file can be and quietly re-compresses anything that scrapes the ceiling. The fix is not to shrink the photo. It is to keep the pixel dimensions high and bring the file size down to each platform's limit — a target-size compression job, not a resize. Sukat does it in the browser, so a catalog of product shots never leaves the device.
The contradiction every seller hits
A modern phone shoots 12 to 50 megapixel photos that weigh several megabytes each. Marketplaces want those big dimensions, because buyers zoom in to check stitching, texture, and condition before they commit. But the same platforms also cap how heavy an upload can be, and they re-encode anything that gets close to the ceiling.
Drop a raw 8 MB photo into a listing and one of two things happens: the upload stalls, or the platform crushes it with its own compression and the result comes back softer than the file you started with. The pixels were never the problem. The bytes were.
What each marketplace actually requires
Three of the biggest marketplaces, three different sets of numbers:
| Marketplace | Minimum | Recommended for zoom | File-size cap | Main-image notes |
|---|---|---|---|---|
| Etsy | 2000 px shortest side | 3000 px square | ~1 MB (heavier can fail) | Square thumbnail crop; JPG or PNG |
| eBay | 500 px longest side | 1600 px | 12 MB per image | 1:1 or 16:9; no text or watermarks |
| Amazon | 1000 px longest side | 2000–3000 px square | 10 MB per image | Pure white background, product 85%+, no WebP |
A few details behind the table that decide whether a listing looks sharp or soft:
- Etsy flags that listing photos over 1 MB may not finish uploading on a slower connection, and it re-compresses images on upload to speed up its pages. Staying under roughly 1 MB while holding 2000 px or more is the sweet spot — big enough for crisp zoom, light enough that Etsy leaves it alone.
- eBay only turns on its enhanced zoom viewer at around 800 px and it looks best at 1600 px on the longest side. It accepts files up to 12 MB and as many as 24 photos per listing, so headroom is generous — the trap is uploading a 500 px image that technically passes but fails the zoom test.
- Amazon will not enable zoom below 1000 px, requires the main image to sit on a pure white background (RGB 255, 255, 255) with the product filling at least 85% of the frame, rejects anything over 10 MB, and — unlike eBay — does not accept WebP at all. JPEG is the safe format there.
Compress the weight, not the dimensions
The instinct is to shrink the image until it fits the cap. That is the wrong lever. Shrinking pixels kills the zoom that sells the product. The right move is to hold the dimensions at 2000 to 3000 px and lower the file size until it clears the ceiling, which means adjusting compression, not resolution.
Doing that by hand is guesswork: drop quality to 80, export, check the size, still too big, try 60, now the edges look rough. Sukat runs a binary search on the quality instead. You give it a target — say, under 1 MB — and it converges on the highest quality that still fits inside that ceiling. The 3000 px dimensions stay exactly as they were; only the bytes come down.
The one-tab workflow
- Drop the photo in. JPG, PNG, WebP — or an iPhone HEIC, which Sukat decodes right in the page. No app to install, nothing uploaded.
- Crop to a square. All three marketplaces crop their thumbnails to 1:1, so framing the shot square stops the platform from lopping off the edge of the product. The crop runs in the same tab as the compression.
- Set the target and format. Enter the file-size ceiling — under 1 MB for Etsy, comfortably below the 10 to 12 MB caps for Amazon and eBay — and choose JPEG output. Because Amazon rejects WebP, JPEG is the one format that uploads cleanly to all three. Click convert, and the file lands under the ceiling at full resolution.
Cropping and compression both run in the browser through the Canvas API, so a catalog of client product shots never touches a server. Switch to airplane mode after the page loads and it still works. You can crop and compress in one pass, or set any custom ceiling with Reduce Image Size in KB.
Frequently asked questions
Will compressing make my photos blurry when buyers zoom?
No — as long as the dimensions stay high. Blur comes from uploading an image below the zoom threshold, or from letting the marketplace re-compress a file that was too heavy. Holding 2000 to 3000 px and compressing only the file size keeps the zoom sharp.
What size should an Etsy listing photo be?
At least 2000 px on the shortest side, with 3000 px better for crisp zoom, and ideally under 1 MB so it uploads cleanly and Etsy does not re-compress it. A square 1:1 frame is the most reliable choice across Etsy's thumbnail crops.
Does this work with iPhone photos?
Yes. iPhone photos are usually HEIC, and Sukat decodes HEIC in the browser. Drop the HEIC in, crop, set the target, and export a JPEG that is ready to upload.
Do my product photos get uploaded anywhere?
No. Cropping and compression both run locally in your browser. The image never reaches a server — which matters when the photos are a client's catalog or an unreleased product.
About Sukat
Sukat builds free, privacy-first browser tools for compressing images and verifying published content. Everything runs in your browser — nothing is uploaded.
