Optimize · Lanczos + sharpening
Upscale Image
Crisp, clean 2x and 4x enlargements for print and web. Advanced resampling and sharpening — not AI hallucination: what's in your photo stays true.
Honest upscaling: resampling, not hallucination
A quick word about how this tool is different. “AI upscalers” run your photo through a generative model that invents plausible detail — sometimes beautifully, sometimes by giving your kid an extra knuckle or rewriting the text on a sign. This tool doesn't invent anything. It enlarges with Lanczos resampling, the gold-standard interpolation filter used in professional imaging pipelines, then applies a calibrated unsharp mask to restore the edge contrast that any enlargement softens. Every pixel in the result is derived from your photo. For print work, product shots, documents and archival scans — anywhere accuracy matters — that's exactly what you want.
It's also why there are no limits here. The popular free upscalers cap input at about 6MB and a couple of images per day, because GPU servers are expensive. This runs on your device: a full-resolution 48MP phone photo, a 30MB scan — all fine, all free, as many as you like.
When to use 2x vs 4x
- 2x is the sweet spot — prints one size up, sharper thumbnails-to-full-size, recovering images saved too small.
- 4x works best on clean, sharp sources like screenshots, logos rendered as PNG, and scans. Heavily compressed JPGs will faithfully enlarge their compression artifacts too — fix those first with the compressor at high quality if needed.
- Sharpening slider: the default suits photos; nudge it down for soft portraits, up for text and line art.
The before/after slider shows a live preview comparing a standard browser enlargement against the Lanczos + sharpening result, so you can judge with your own eyes before downloading.
Common questions
Is there really no size limit?
Your browser's canvas memory is the only ceiling (about 16,384px per side). There's no upload, so there's no server limit to hit.
Why not use AI?
Generative upscalers change your image content. For the many uses where fidelity matters more than invented texture, classic resampling done well is the better — and more honest — tool.
What's the best format to save in?
PNG keeps every pixel exactly. Use JPG or WebP when file size matters more — at quality 92 they're visually identical for photos.