Upscale an image 4x

Make an image 4 times as wide and as tall, with 16 times the pixels. Choose Fast mode, or AI mode on supported devices, and compare with a slider. Free.

Before you start

4× means each side becomes four times as long, so a 500 × 400 photo becomes 2000 × 1600 pixels. That is 16 times as many pixels, the biggest jump this tool makes. It suits small pictures: an avatar, a product thumbnail, an old scan or a low-quality download.

The biggest picture the tool makes has 16,777,216 pixels, which is 4096 × 4096 for a square. So a photo of up to about 1 megapixel, such as 1280 × 800, can go 4×. Bigger photos get the biggest step that fits (3×, 2× or less), and the tool tells you.

Tips

Try both modes on the same photo. For a small picture both results are kept, so you can switch between them and look at each one with the slider.

AI mode is worth trying on blocky, over-compressed JPEG images. On a picture that is already clean, the difference between the two modes is small, and on dark, noisy photos AI can score lower than Fast when compared with the original, because it smooths the noise.

If 4× looks too soft, go back and choose 2×. A smaller step keeps more of what is really in the photo.

Questions and answers

Will a 4x picture look sharp?

It will look bigger and cleaner, not as sharp as a photo taken at that size. 4× spreads the same detail over 16 times the pixels. AI mode can add believable texture, but it cannot know what was really there.

Why did I get 3x or 2x when I asked for 4x?

The biggest picture is 16,777,216 pixels, the same limit on every device, and no side longer than 8,192 pixels. A larger photo would go over that at 4×, so the tool uses the biggest step that fits and says so.

How long does 4x take?

Fast mode takes a few seconds on a laptop, and more on a phone. AI mode takes longer, and longer again on a phone. If the job would take more than about 3 minutes, the tool says so and offers Fast mode instead. You can cancel at any time.