AI Image Upscaler

Upload your photo, upscale and sharpen it with AI — optionally colorize black and white photos too.

This tool requires JavaScript to run the actual AI processing in your browser. Please enable JavaScript to use it.

AI Image Upscaler

Upload a low-resolution photo, upscale it 4x and sharpen it with AI, and optionally colorize black and white photos too. Free, runs entirely in your browser.

How it works

Upload your photo. JPG, PNG, or WEBP — drag & drop or click.
Choose upscale, colorize, or both. If colorize is checked, it's applied first, then upscaling.
Download your sharpened photo. With 4x the resolution.

Why Stelluna

Free — no sign-up needed
Runs in Your Browser — your photo never leaves your device
Fast — results in seconds

Frequently Asked Questions

Is it free?
Yes, no account needed.

Does my photo get uploaded anywhere?
No, upscaling and colorizing run entirely in your browser.

How much does it upscale by?
4x — input is capped at 480px on the longest side before upscaling.

Do I need to sign up?
No.

Can I colorize and upscale at the same time?
Yes, check the colorize box and the photo is colorized first, then upscaled.