How to Bulk Resize Product Images for E-commerce

My client had 500 product photos that needed to be resized for their Shopify store. By hand, that's 20+ hours of work. With batch processing, I finished in 15 minutes.

Why Product Image Size Matters

• Conversion Rate: High-quality images increase sales by up to 30%
• Page Speed: Oversized images kill mobile conversions
• Platform Requirements: Each marketplace has specific size rules
• Consistency: Uniform sizing looks professional

Platform-Specific Requirements

Amazon

• Main Image: 2000 × 2000 px (for zoom feature)
• Minimum: 1000 × 1000 px
• Format: JPEG, PNG, GIF
• Background: Pure white (RGB 255,255,255)

Shopify

• Recommended: 2048 × 2048 px (square)
• Maximum: 4472 × 4472 px
• Max file size: 20MB
• Format: JPEG, PNG, GIF, WebP

Etsy

• Minimum: 2000 px (shortest side)
• Ideal: 2000 × 2000 px
• Aspect ratio: 4:3 or 1:1
• Max file size: 3MB per image

eBay

• Minimum: 500 × 500 px
• Recommended: 1600 × 1600 px
• Max file size: 12MB

Bulk Resizing Workflow

1. Organize originals: Create "originals" folder, never touch it
2. Test settings: Resize 5 images first to verify quality
3. Batch process: Use bulk resizer with consistent settings
4. Quality check: Spot-check 10% of processed images
5. Organize output: Create folders by platform/size

Best Practices for Product Photos

• Consistent aspect ratio: All products same shape for uniform grid
• White background: Required by Amazon, recommended everywhere
• Product fills 85%: Not too small, not cropped
• File naming: SKU-color-angle.jpg (e.g., SHOE123-red-front.jpg)
• Compress after resize: Keep under 500KB for fast loading

My Folder Structure