Resize your images.
Drop an image or paste its URL, and we'll generate every size your responsive layout needs. You also get a blurred placeholder for that smooth loading effect.
Choose your image
Drop an image here or click to pick one
PNG, JPG, WebP up to 10 MB
Resize settings
Blur placeholder (LQIP)
Tiny blurred image for loading effect
Why Responsive Images Matter for Web Performance
Adaptive Breakpoints
Modern browsers download different image assets depending on the user's screen width. Instead of serving a heavy desktop image to a mobile phone, responsive breakpoints serve smaller files to smaller screens. This cuts page weight and speeds up loading.
WebP and Compression
AltImg generates files in WebP format, which reduces file sizes by up to 30% compared to JPEG or PNG without losing visible details. This helps you save user bandwidth and keep page loading fast.
Blur-Up Loading (LQIP)
Low Quality Image Placeholders (LQIP) are tiny, highly-compressed image representations loaded inline as a base64 background. When the main image finishes loading in the background, a transition reveals it. This prevents layouts from shifting.
Clean Code Snippets
The tool generates HTML <picture> and srcset code blocks. You can copy and paste them directly into your templates, saving you from writing responsive source logic by hand.