AI Image Upscaler
Upscale images 2x or 4x with AI — free
🔒 Your image is processed entirely in your browser. Nothing is uploaded to any server.
How to Use AI Image Upscaler
Upload your image
Drag and drop any JPG, PNG, or WebP image. For best speed, use images under 1024x1024. Your image stays in your browser and is never uploaded.
Choose upscale mode
Pick from 3 modes: 2x Fast (3.9MB Swin2SR), 2x Quality (8.6MB APISR GAN for sharper results), or 4x Enlarge (5.0MB APISR). Models download once and are cached.
Download the result
Click Upscale Image and wait 10-30 seconds. Compare original vs upscaled side by side, then download the high-resolution PNG.
Why Choose AllTools AI Image Upscaler?
- ✓ Three AI models: 2x Fast, 2x Quality (GAN), 4x Enlarge
- ✓ Swin2SR and APISR — state-of-the-art super-resolution neural networks
- ✓ Runs 100% in browser — image never uploaded to any server
- ✓ Models cached after first download (3.9-8.6MB) — works offline
- ✓ Side-by-side comparison with dimension display
- ✓ Download as full-resolution PNG without watermark
- ✓ No account, no limits, completely free
- ✓ Works on desktop and mobile browsers
Why Use This Tool
- ★ Complete privacy — your image never leaves your browser, verifiable in DevTools Network tab
- ★ Free forever — no $199 license like Topaz Gigapixel, no per-image fees
- ★ Three quality modes — choose speed vs quality based on your needs
- ★ Tiny models (3.9-8.6MB) — fast download, cached for offline use
- ★ No account, no watermark, no limits — just upload and upscale
How AI Image Upscaling Works
Traditional image resizing (bilinear, bicubic interpolation) simply stretches pixels, producing blurry results. AI upscaling uses neural networks trained on millions of image pairs (low-res and high-res) to learn what detail should exist at higher resolutions. This tool offers two model families: Swin2SR uses a Shifted Window Transformer architecture that processes the image in overlapping patches, generating sharp details while maintaining consistency across patch boundaries. APISR uses a GAN (Generative Adversarial Network) trained specifically for anime and photographic super-resolution, producing perceptually sharper results. All models run via ONNX Runtime in your browser using WebAssembly — no server processing, no upload, complete privacy.
When to Use Each Upscale Mode
Use 2x Fast (Swin2SR, 3.9MB) for quick previews, social media images, and batch workflows where speed matters more than maximum quality. Use 2x Quality (APISR GAN, 8.6MB) for photos you plan to print, portfolio images, or any case where perceptual sharpness is important — the GAN model adds realistic texture detail that the fast model smooths over. Use 4x Enlarge (APISR, 5.0MB) when you need to dramatically increase resolution — turning a 256x256 thumbnail into a usable 1024x1024 image. Note that 4x upscaling works best on images with clear subjects and good original quality. Very noisy or heavily compressed source images may show artifacts at 4x.
Related Resources
Frequently Asked Questions
Is my image uploaded to a server? ▼
How long does upscaling take? ▼
What is the difference between the 3 modes? ▼
What image formats are supported? ▼
Is there a file size or resolution limit? ▼
Does it work offline? ▼
How does this compare to Topaz Gigapixel? ▼
Can I upscale the same image multiple times? ▼
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