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AI Image Upscaler

Upscale images 2× with AI super-resolution — powered by Swin2SR, runs entirely in your browser.

All processing runs entirely in your browser using WebAssembly. No image or text is ever uploaded to a server. First run downloads the AI model (~44–70 MB) and caches it locally — subsequent runs are instant.
Original

Drop an image or click to browse

PNG, JPG, WebP — best results under 512×512 px

Upscaled 2×
Upscale Mode: Swin2SR-Classical AIStatus: No Image

Upscaled result will appear here

AI Image Upscaler — 2× Super-Resolution in Your Browser

This tool uses Swin2SR, a Swin Transformer V2-based image super-resolution model, to double the resolution of images directly in your browser. Swin2SR achieved state-of-the-art results on benchmark datasets when it was published and produces sharp, natural-looking output without the ringing artefacts common in older upscaling methods. The quantised model (~150 MB) downloads once and is cached locally. Works best on images up to 512×512 pixels — larger inputs work but take longer. The output is always a lossless PNG at exactly 2× the input dimensions. Nothing is uploaded to a server.

Built and maintained by Meet Shah · Last updated

What this tool is used for

  • Enlarging a small image where a plain resize would look soft.
  • Recovering usable detail from a low-resolution asset.
  • Upscaling a screenshot for a print or a large display.
  • Getting a larger version of an image whose source has been lost.
  • Comparing an AI upscale against a plain resize.

Frequently Asked Questions

Does upscaling recover lost detail?
No — it invents plausible detail. A model trained on many image pairs predicts what a higher-resolution version would look like, which is a very different claim from recovering what was there. The result can look sharper and be wrong about specifics.
How is it different from bicubic resizing?
Conventional interpolation averages neighbouring pixels, which is why an enlarged image looks soft. A learned model instead generates edges and texture that were never in the source, so it looks sharp — at the cost of hallucinating detail that is not evidence.
Where does that matter?
Anywhere the pixels are evidence. Upscaling a licence plate, a face from CCTV, or a document scan produces a confident image that is a guess, and it has been misused as if it were enhancement. For illustration and print it is fine; for identification it is not.
Why is the first run slow?
Because the model weights download and compile before anything can be processed — tens of megabytes, once, then cached. That cost is what buys running locally, so the image is never uploaded anywhere.
What kind of image upscales best?
Clean sources with clear structure — line art, logos and well-exposed photographs. Heavily compressed JPEGs upscale badly because the model faithfully amplifies the block artefacts, treating compression noise as detail worth reconstructing.

Common errors and gotchas

  • Expecting real detail to be recovered, when the model is inventing plausible detail rather than restoring it.
  • Upscaling faces or text, where invented detail is most obviously wrong.
  • Assuming the first run works offline, when the model downloads once.
  • Upscaling a lossy image, where the model amplifies compression artefacts along with the subject.
  • Using an upscale where the correct fix is to obtain the original at full size.

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