Question 1

Can I upscale pixel art or sprites in the browser without waifu2x?

Accepted Answer

Yes. This page (https://gameimagekit.com/en/tool/ai-upscale) offers Swin2SR / APISR AI super-resolution plus a no-download Lanczos tier. Everything runs locally — nothing is uploaded.

Question 2

Are my images uploaded to a server?

Accepted Answer

No. Both the AI super-resolution models and Lanczos interpolation run locally in your browser. Images are never uploaded, so the whole process stays private and secure.

Question 3

Lanczos vs. AI upscale — which should I pick?

Accepted Answer

Lanczos is classic high-quality interpolation: zero download, instant output, great for pixel assets and UI icons that need crisp enlargement. AI upscale (Swin2SR / APISR) actually reconstructs detail and texture for better results, but requires a first-time model download and takes longer. Prefer Lanczos for pixels/icons, AI for photos/illustrations.

Question 4

General Photo vs. Anime AI models?

Accepted Answer

The General Photo tier is based on Swin2SR real-world SR and generalizes well to photos, icons and game assets. The Anime tier is based on APISR, optimized for the lines and detail of anime, illustration and line art. Just pick by content type.

Question 5

Why do I have to wait for a download on the AI tiers?

Accepted Answer

AI super-resolution needs to download a model (~50–70MB). It downloads once on first use and is cached by the browser, so subsequent runs are much faster. The Lanczos tier needs no download at all.

Question 6

Why is upscaling large images slow?

Accepted Answer

Super-resolution compute grows with pixel count, so large images are auto-tiled and stitched, which takes longer. When the browser lacks WebGPU it falls back to WASM (slower). Use a recent Chrome / Edge to enable WebGPU acceleration.

AI Image Upscaler