Local AI Image Upscaler
Multiply your photos' resolution ×2 or ×4 with Swin2SR neural networks running on your own GPU. Nothing ever gets uploaded.
Multiplies resolution (×2 or ×4 depending on model).
Real-ESRGAN: the standard for real photos. Much faster per tile. Max side: 2048px.
Built by
Miguel Ángel Colorado Marin (MACM)
Built by
Miguel Ángel Colorado Marin (MACM)
Full-Stack Developer · Guadalajara, España
I develop web apps, digital tools and full projects — from design to deployment.
Upscaling a photo isn't stretching it: classic interpolation multiplies pixels into blurry edges and stair-stepping. Super-resolution models like Swin2SR "invent" the missing detail, reconstructing sharp edges, textures and hair from what they learned across millions of images. This tool runs those models inside your browser through WebGPU (with automatic CPU fallback if your device doesn't support it): processing happens on your device, with no upload queues, no paid tiers and no usage limits. Choose between fast ×2, higher-detail classical ×2, or the real-world photography ×4 model; compare original and result with the draggable divider and download watermark-free PNGs.
Features
- ✓Two modes: upscale resolution (×2/×4) or enhance only without resizing
- ✓3 Swin2SR models with tile-based inference: handles large images without exhausting memory
- ✓WebGPU when available; CPU (WASM) as automatic fallback
- ✓Before/after comparison with draggable divider and visible process time
- ✓100% local: your image never leaves your device
How to upscale an image with AI?
- 1
Pick the model
Fast ×2 for small shots; real-world ×4 for photography.
- 2
Drop your image
The model downloads only on first use and stays cached.
- 3
Compare by dragging
The divider splits original and result in real time.
- 4
Download the PNG
At full resolution, watermark-free, no sign-up.
Frequently asked questions
Why does it sometimes take over a minute?
The model processes the image in 256px tiles on your CPU (via WASM) to avoid exhausting memory; time grows with tile count. The first run also downloads the model, which is then cached.
What does "enhance only" mode actually do?
It runs the same super-resolution model and then rescales the result back to your original resolution with high-quality interpolation. The net effect is noise cleanup and detail enhancement without changing size — great for noisy or compressed photos you don't want enlarged.
Does it work on mobile?
It may work with tiny images, but phones run short on RAM and CPU for the big models. Our philosophy is a powerful honest tool over a crippled one: for ×4 use desktop.
How is this different from other web upscalers?
Two things: privacy and cost. Here the model runs in YOUR browser — the image is never sent to any server — and there are no credits, subscriptions or watermarks, because there's no backend to pay for.
Related tools
Embed AI Image Upscaler on your site
Add AI Image Upscaler to any web page with a simple iframe. Free, with attribution to miguelacm.es.
<iframe
src="https://miguelacm.es/embed/image-upscaler"
width="100%"
height="700"
frameborder="0"
title="AI Image Upscaler — miguelacm.es"
></iframe>