Generating high-resolution product photos is only half the battle. The other half is actually getting those images uploaded to marketplaces without them being rejected, silently compressed into mush, or stuck in a queue because the file is too large.
If you've been generating 4K product images with CatalogX or any other tool, you've probably already run into this: a 4K PNG can be 15-25MB, and most Indian marketplaces cap uploads at 5-10MB. So what do you do? This guide walks you through the exact upload requirements for each platform and the fastest ways to prepare your images.
Platform Upload Limits at a Glance
Before you prepare a single image, here's what each marketplace actually accepts:
| Platform | Max File Size | Formats | Max Resolution | Aspect Ratio |
|---|---|---|---|---|
| Amazon India | 10 MB | JPEG, PNG | 10,000 x 10,000 px | 1:1 preferred |
| Flipkart | 10 MB | JPEG, PNG | No stated limit | Flexible |
| Myntra | 5 MB | JPEG preferred | No stated limit | 3:4 required |
| Ajio | 5 MB | JPEG | No stated limit | 3:4 required |
| Shopify | 20 MB | JPEG, PNG, GIF, WebP | 4472 x 4472 px | Flexible |
The File Size Problem with 4K
A 4K image is typically 4096x6144 pixels in portrait orientation. At that resolution, file sizes vary dramatically by format:
- 4K PNG (lossless): 15-25MB -- exceeds every marketplace limit
- 4K JPEG at quality 95: 8-15MB -- exceeds Myntra/Ajio, may exceed Amazon/Flipkart
- 4K JPEG at quality 90: 3-8MB -- fits Amazon/Flipkart, usually fits Myntra
- 4K JPEG at quality 85: 2-5MB -- fits all marketplaces
The solution is straightforward: convert to JPEG before uploading. PNG is great for archival and editing, but no marketplace needs lossless compression for product listings. JPEG at quality 85-92 is visually indistinguishable from PNG for product photos, and the file size drops by 70-90%.
Step-by-Step: Prepare 4K Images for Each Marketplace
Here are the exact settings to use for each platform:
Amazon India
- Convert PNG to JPEG at quality 92
- You can upload full 4K (4096x6144px) if the file stays under 10MB
- If the file exceeds 10MB, resize to 2500x3750px -- this still enables maximum zoom quality
- Amazon's zoom feature requires 1600px+ on the longest side, so even 2500px is well above the threshold
- White background required for the main image
Flipkart
- JPEG at quality 90
- 2000x3000px is the sweet spot -- large enough for zoom, small enough for reliable uploads
- Full 4K works if the file is under 10MB, but Flipkart compresses images server-side anyway
- Beyond 2500px, you get diminishing returns as the platform downscales for display
Myntra
- Must be 3:4 ratio -- this is non-negotiable. Images in other ratios get rejected
- Crop to 2160x2880px or 1620x2160px for the best balance of quality and file size
- JPEG at quality 85-90 to stay under the 5MB limit
- Myntra serves images at around 1500px wide to customers, so anything above 2160px width offers no visible benefit
Ajio
- Same as Myntra: 3:4 ratio, JPEG, under 5MB
- 2160x2880px at quality 85 is ideal
Shopify (D2C Store)
- Most flexible -- supports up to 20MB and multiple formats including WebP
- You can upload full 4K here, but consider page speed: a product page with 6 images at 4K each will load slowly on mobile
- Recommendation: use 2K (2048x3072px) for listing images, enable lazy loading, and let Shopify's CDN serve optimised versions
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Quick Conversion Methods
You don't need Photoshop to convert and resize product images. Here are the fastest methods:
Free online tools
- Squoosh.app (by Google) -- drag and drop, adjust quality with a slider, see file size in real time. Best for one image at a time.
- TinyPNG -- supports batch conversion of up to 20 images at once. Handles both PNG-to-JPEG conversion and compression.
- iLoveIMG -- bulk resize and format conversion with preset dimensions.
Command line (for tech-savvy sellers)
If you have ImageMagick installed, you can convert an entire folder in one command:
mogrify -format jpg -quality 90 *.png
# Resize to 2500px wide, maintain aspect ratio
mogrify -resize 2500x -quality 90 -format jpg *.png
# Crop to 3:4 ratio (for Myntra/Ajio) and resize
mogrify -gravity center -crop 3:4 -resize 2160x2880 -quality 88 -format jpg *.png
Bulk conversion tips
- Process all images for one marketplace at a time -- use the same settings for consistency
- Name output files with the marketplace suffix (e.g.,
kurta-red-myntra.jpg) so you don't mix up versions - Keep your original 4K PNGs as masters -- never overwrite them with compressed versions
Do Marketplaces Actually Benefit from 4K?
The short answer: yes, but only up to a point. Here's what each platform actually does with your images:
- Amazon: Zoom requires 1600px+ on the longest side. 4K (6144px) is overkill for zoom but ensures maximum quality even after Amazon's own compression. The practical sweet spot is 2000-2500px.
- Flipkart: Benefits up to around 2000px. Beyond that, Flipkart's server-side compression negates the extra resolution. Uploading at 4K vs 2K produces nearly identical results on the customer's screen.
- Myntra: Benefits up to around 2000px. Myntra serves images at a fixed size in their app and compresses aggressively. Going above 2160px wide is wasted bandwidth.
Aspect Ratio Considerations
This is where most sellers run into trouble. CatalogX generates images in a 2:3 portrait ratio:
- HD: 1024 x 1536 px (2:3)
- 2K: 2048 x 3072 px (2:3)
- 4K: 4096 x 6144 px (2:3)
Amazon and Flipkart accept 2:3 images without issue. But Myntra and Ajio require 3:4 ratio. A 2:3 image is taller and narrower than 3:4, so you need to crop.
How to crop 2:3 to 3:4 without losing the garment:
- Open the image in any editor (even Preview on Mac or Photos on Windows)
- Crop from the bottom -- most CatalogX-generated images have extra floor/ground space at the bottom that can be trimmed
- For a 4K image (4096x6144), crop to 4096x5461 for exact 3:4 ratio. This removes 683px from the bottom -- usually just floor space.
- For a 2K image (2048x3072), crop to 2048x2731. This removes 341px from the bottom.
- If the garment extends to the bottom of the frame, crop equally from top and bottom to center the product
After cropping to 3:4, resize down to your target dimensions (2160x2880 for Myntra) and export as JPEG.
Frequently Asked Questions
Amazon will not reject images based on pixel dimensions alone -- they accept up to 10,000x10,000 pixels. However, they will reject files over 10MB. A 4K PNG can easily exceed this limit. Convert to JPEG at quality 90-92 to bring the file size under 10MB while keeping full 4K resolution. Amazon actually benefits from high-resolution images because they enable the zoom feature, which requires at least 1600px on the longest side.
Myntra prefers JPEG format with a strict 3:4 aspect ratio. The recommended resolution is 1500x2000 pixels or higher. File size must be under 5MB. If you have a 4K image, crop it to 3:4 ratio (e.g., 2160x2880 pixels) and export as JPEG at quality 85-90. This will typically produce a file between 2-4MB, well within Myntra's limit.
For a few images, use free online tools like Squoosh.app or TinyPNG. For bulk conversion, ImageMagick is the most reliable command-line tool: run 'mogrify -format jpg -quality 90 *.png' in your image folder. On Mac, you can also select multiple PNGs in Finder, right-click, and use Quick Actions to convert. CatalogX exports in both PNG and JPEG formats directly.
Yes, Flipkart applies its own compression and resizing to uploaded images. It typically serves images at around 1000-1500 pixels wide to customers, regardless of the upload size. However, uploading higher resolution images (2000px+) gives Flipkart a better source to compress from, resulting in sharper final images. Uploading beyond 2500px provides diminishing returns as the platform compresses heavily anyway.
No. WhatsApp compresses all images aggressively regardless of the original size, typically down to around 1000px on the longest side at moderate JPEG quality. Uploading 4K images to WhatsApp wastes your upload bandwidth and storage without any visual benefit. For WhatsApp catalogs, 1200x1600 pixels at JPEG quality 85 is the sweet spot -- small enough for fast uploads, high enough that WhatsApp's compression still produces acceptable results.