Images never leave your device
No account required
Multiple sizes at once
JPEG / PNG / WebP supported
Upload an image to see resized previews here
Upload an image to generate HTML code
Default: 320, 640, 768, 1024, 1280, 1920px
What is Responsive Image Generator?
Responsive images use srcset and sizes attributes to serve the optimal image for each user's device and screen size. Combined with <picture>, you can also switch between formats.
This tool generates multiple resized images and HTML code from a single image, all processed in your browser.
Key Features
- 📏 Batch resize with custom breakpoints
- 🖼️ JPEG / PNG / WebP output
- 📋 Auto-generate img+srcset / picture HTML
- 🗜️ Quality control for file size optimization
- ⬇️ Download all sizes at once
- 🔒 All processing in your browser
How to Create Responsive Images
Step 1: Upload Image
Upload a high-resolution source image.
Step 2: Set Breakpoints
Configure the output widths. Use defaults or customize.
Step 3: Generate & Download
Click "Generate Code", copy HTML, and download images.
How srcset, sizes & picture Work
srcset provides browsers with multiple image candidates. Combined with sizes, the browser automatically selects the optimal image for the viewport.
Attributes & Elements
| Attribute/Element | Description | Example |
|---|---|---|
srcset | Image candidate list (w/x) | img-320w.webp 320w, ... |
sizes | Display width conditions | (max-width:640px) 100vw |
<picture> | Format/resolution switching | <source type="image/webp"> |
<source> | Candidate within picture | media, srcset, type |
Frequently Asked Questions
- Q. w vs x in srcset?
- A. w represents the image's actual width in pixels; x represents pixel density. w is more flexible and recommended.
- Q. Browsers that don't support WebP?
- A. Use picture element fallback with JPEG/PNG.
- Q. Is any data sent to a server?
- A. No. All processing happens in your browser.
- Q. Can I generate sizes larger than the original?
- A. Upscaling degrades quality. Stay within original dimensions.
- Q. Download format?
- A. Files are downloaded individually.
Responsive Image Use Cases
Web Optimization
Serve optimal sizes per device to improve Core Web Vitals.
Mobile First
Light images for mobile, rich images for desktop.
Art Direction
Different crops per viewport using picture element.
E-Commerce
Optimize product images for faster load and better conversions.