How to upscale a screenshot with AI on Mac
The short answer: macOS has no built-in AI upscaler — Preview can only resize, which leaves a low-res screenshot soft and blocky. To genuinely enhance one you need an AI model. ShotScreen enlarges an image up to 4× with on-device Real-ESRGAN and lets you check the result on a before/after slider. Open the image, choose Upscale, done.
Step by step with ShotScreen
- 1
Open the low-res image
Capture the screenshot (⌘⇧4 for an area) or drag an existing image onto ShotScreen. It appears as a live preview thumbnail.
- 2
Choose Upscale
Open Resize / Upscale from the action bar and pick AI upscaling. Set 2×, 4× or a custom target width — ShotScreen uses the Real-ESRGAN model for photographic detail.
- 3
Let it enhance on-device
ShotScreen runs the model locally, tile by tile with feather-blending so there are no visible seams, and shows progress as it goes. Larger images take a few seconds.
- 4
Compare, then save
Drag the before/after slider to check the result against the original, then save the enlarged PNG, drag it into another app or keep editing.
Why Preview's resize is not enough
Resizing in Preview simply stretches the pixels you already have, so a small or blurry screenshot only gets bigger and softer. An AI upscaler like Real-ESRGAN reconstructs plausible detail — sharper text edges, cleaner lines — instead of interpolating. That is the difference between "larger" and "actually better".
Everything stays on your Mac
The upscaling model runs locally through Core ML — no upload, no account, works offline. Large targets are handled in tiles with feather-blending so the enlarged image has no visible seams, and a before/after slider lets you compare against the original before you save.
FAQ
Does macOS have a built-in AI upscaler?
No. macOS can resize an image in Preview, but that just interpolates pixels and leaves the result soft. There is no native AI upscaler, which is why a dedicated tool is needed to genuinely enhance a low-res screenshot on a Mac.
How much can ShotScreen enlarge an image?
ShotScreen upscales 2×, 4× or to a custom target width using Real-ESRGAN. Very large targets are processed in tiles with feather-blending, so the output has no visible seams.
Is the upscaling done on-device?
Yes. Real-ESRGAN runs locally on your Mac through Core ML. Nothing is uploaded, so it works offline and your screenshots stay private.
Enhance low-res screenshots on your Mac
ShotScreen is free to use, with 5 popup-free screenshots a day. AI upscaling and every other tool are included from the start.
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