About us

4K Photo Converter is a free online tool that turns small, soft or low-resolution photos into sharp, high-resolution images. We built it because most "AI upscalers" ask you to create an account, cap how many images you can process, stamp a watermark on the result — and quietly upload your personal photos to a server you know nothing about.

We think enlarging a photo should be simple, free and private. So that's what we made.

What we do

Drop in a JPG, PNG or WebP image and 4K Photo Converter uses an open-source super-resolution neural network (ESRGAN) to reconstruct detail as it enlarges the picture — up to 4K resolution, or 2×, 4× and 8× its original size. You can compare the before and after side by side and download the result as a PNG with no watermark.

Privacy by design

The whole upscaling process runs on your own device, inside your browser tab, usingTensorFlow.js and your computer's GPU. Your photos are never uploaded to us or anyone else — we couldn't see them even if we wanted to. You can read the details in our Privacy Policy.

What we believe in

• Free to use. No sign-up, no subscription, no daily limits and no watermarks.
• Your photos stay yours. Images are processed locally and never leave your device.
• Honest results. AI upscaling predicts plausible detail — it can't recover information that was never captured, and we say so.
• Built on open source. The tool is powered byUpscalerJSand openly licensed models.

Get in touch

Have feedback, found a bug or have an idea for a feature? We'd love to hear from you — visit ourContact page.