Upscale images 4× with AI that never sees them
Real-ESRGAN super-resolution running entirely in your browser. No uploads, no accounts, no watermarks: your photos stay on your device.
Drop an image here, or paste from clipboard
Loading the AI engine: about 10 MB on the first visit, cached after that. You can drop an image already.
WebGPU accelerated~5 MB model, cached locallyLossless PNG out
How it works
Drop an image
Drag, click, or paste from your clipboard. The file is opened right in this tab; nothing is transmitted.
AI rebuilds the detail
Real-ESRGAN processes the image in 192-pixel tiles on your GPU, inferring realistic texture at 4× the resolution.
Download the 4× PNG
800×600 becomes 3200×2400. Watch the before/after slider, then save the lossless result.
Curious what "AI upscaling" actually does? Read the plain-English guide.
Everything you'd pay for elsewhere, free
Private by architecture
The network tab stays empty: inference happens in your browser, so there is no server that could store, scan, or leak your images.
Free and unlimited
No credits, no daily quota, no account. Your own GPU does the work, so we don't need to charge for compute.
WebGPU accelerated
Runs on your graphics card via WebGPU where available. In our tests a 1-megapixel photo finishes about 6× faster than the multi-threaded CPU fallback.
Real-ESRGAN quality
The same open-source super-resolution model used by professional tools, rebuilding texture instead of just stretching pixels.
Works offline
After the first visit the app and its 5 MB model are cached. Load the page, go offline, keep upscaling.
Lossless PNG output
Every result downloads as a clean PNG at 4× resolution: no watermarks, no compression, no strings.
Why on-device beats the cloud
Most online upscalers send your image to a server farm, run the model there, and send the result back. That architecture is why they need accounts, quotas, and privacy policies with teeth. Doing the same work on your own hardware makes those problems disappear.
| Typical cloud upscaler | This tool | |
|---|---|---|
| Your image travels | To their servers and back | Nowhere, it stays in the tab |
| Cost | Free trial, then credits | Free, unlimited |
| Limits | Daily quotas, queue times | Only your device's memory |
| Account required | Usually, for full size | Never |
| Watermarks | Common on free tiers | None |
| Privacy promise | "Auto-deleted after 24 to 72 hours" | Nothing to delete, no upload |
Questions, answered
Curious what "AI upscaling" actually does? Read the plain-English guide.
Is this image upscaler really free?
Yes: free and unlimited, with no account, no credits, and no watermarks. The AI runs on your own hardware instead of our servers, so serving the tool costs almost nothing and there's nothing to meter.
Are my images uploaded to a server?
No. The neural network runs inside your browser using WebGPU (or WebAssembly as a fallback). Your image is never transmitted anywhere. You can verify this in your browser's network inspector, or load the page and then upscale with Wi-Fi turned off.
What AI model does it use?
Real-ESRGAN (the realesr-general-x4v3 variant), a widely used open-source super-resolution network, running via ONNX Runtime Web. The model itself is only about 5 MB and is cached by your browser after the first visit.
How big can my image be?
Output is limited by your device's memory, since 4× upscaling multiplies pixel count by 16. On desktop the input limit is about 6 megapixels (e.g. 3000×2000); on phones about 2 megapixels. Larger images are reduced to fit automatically before upscaling. Accepted inputs: PNG, JPEG, WebP, GIF, BMP, AVIF, HEIC and TIFF.
Which browsers are fastest?
Recent Chrome, Edge, and Safari use WebGPU, which in our tests runs larger images around 6× faster than the WebAssembly fallback. Every modern browser works; the tool automatically picks the fastest engine your device supports.
Does it work on photos of people?
Yes, though the general-purpose model doesn't include a dedicated face-restoration pass. It excels at photos, artwork, game textures, logos, and old low-resolution images. Heavily compressed faces may keep some softness.
What format is the result?
A lossless PNG at 4× the original width and height: a 800×600 image becomes 3200×2400. Everything happens locally, so the download is instant once processing finishes.
What if I need more than 4×, face restoration, batch, or video?
This tool does one job: a single image, 4×, on your device. For 8× to 16×, a dedicated face enhancer, batch folders, colorizing or video, Higgsfield Upscale does all of that in the cloud (paid plans; the image is uploaded to their servers), and Topaz Gigapixel is the desktop option (paid, Windows and Mac). Nothing here changes: the free tool stays free, unlimited and on-device. higgsfield.ai