Upscayl

FreeFree

Design Software

Free, open-source AI image upscaler. Enlarges and sharpens designs to print-ready resolution — runs locally on your computer.

How to use for Merch

Download Upscayl (free, desktop app) and use it to upscale AI-generated images to 4500×5400px or higher without losing quality. Select 'Real-ESRGAN' model for illustrations and 'UltraSharp' for detailed artwork. Export as PNG. Unlike web-based upscalers, Upscayl runs entirely on your machine — no upload limits, no watermarks, and no subscription fees.

Pro Tips

1Use 'Real-ESRGAN' for flat illustrations and vector-style art — sharpest results
24x upscale on a 1024px image gives you a 4096px file — more than enough for Merch
3Batch mode: upscale your entire design folder overnight with no per-image limits
4Run on GPU for 10x faster processing — works with both NVIDIA and Apple Silicon
5Free forever — no account needed, no watermarks, unlimited use

Ready to try Upscayl?

Free to start — no credit card required.

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