ClearPixUpscale image to HD — free & private
ClearPix upscales images up to 4× with Real-ESRGAN super-resolution, entirely in your browser. The AI model (4.9 MB) runs on your GPU via WebGPU or on the CPU via WebAssembly, processing large images in overlapping tiles. It is free with no sign-up and no watermark on exports. Source images up to 2048 px on the longest side are supported (1400 px without WebGPU).
Enlarge images up to 4× with Real-ESRGAN super-resolution, running entirely in your browser. No upload, no queue, no watermark on your export.
Drop your image here, or click to browse
PNG / JPG / WebP — longest side up to 2048px for in-browser processing · You can also paste an image (⌘V)
What local processing means
Unreleased illustrations and family photos are enlarged directly in your browser, not sent to an image-processing server. Real-ESRGAN, ONNX Runtime Web and any public examples still download before the first run; the source picture and result remain on your device. After the required model and application files are cached, supported 2× and 4× runs work offline. Anonymous usage events do not contain your image or filename.
What browser AI actually uploadsTrust CenterPublic quality evidence
What is AI super-resolution?
Real-ESRGAN is a neural network trained on real-world image degradation. Unlike a simple resize, it reconstructs plausible high-frequency detail — sharper edges, recovered texture, cleaned-up compression artifacts. ClearPix runs the model in overlapping tiles on your own GPU (WebGPU) or CPU (WebAssembly), so even large images process safely without any server.
When to use 2× vs 4×
- 4×— small thumbnails, compressed social-media saves, AI-art drafts.
- 2×— moderate enlargements where you want a natural, less sharpened look.
- For very large sources, downsize first and let the model rebuild the detail.
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Image upscaling FAQ
How do I upscale an image to 4K for free?
Drop the image in, pick 2× or 4×, and press Upscale — the Real-ESRGAN model rebuilds fine detail instead of just stretching pixels. With 4×, a 960×540 source becomes 3840×2160 (4K). It is free and unlimited, and the export carries no watermark. The first run downloads the 4.9 MB model once and caches it.
What is the maximum image size the upscaler supports?
The source can be up to 2048 px on the longest side with WebGPU (1400 px on the WebAssembly fallback) — larger files can be shrunk in one click first. Output is limited by your device memory rather than a fixed quota, and tiled processing keeps big jobs stable.
Does upscaling reduce quality or add artifacts?
Super-resolution reconstructs plausible detail, so results look sharper than a plain resize. On very compressed or noisy sources the AI can invent texture — lower the sharpening slider for a softer, more natural look. Your original is never recompressed: you export a fresh PNG, JPG or WebP.
Are my images uploaded when I upscale them?
Never. The model executes locally via ONNX Runtime Web — open the network panel and nothing is sent while processing. After the first download the model is cached in your browser, and the tool keeps working offline.
Only process images you own or have explicit permission to modify.
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