Upscale an image to 4K

Make a picture 3840 pixels on its long side, the width of a 4K screen, in Fast mode or AI mode on supported devices. Free, and nothing is uploaded.

Before you start

A 4K screen is 3840 × 2160 pixels. A smaller picture looks soft on it, for a wallpaper, a slide or a video thumbnail. This page opens the enlarger with a 4K choice: the picture is made so that its long side is 3840 pixels, and its shape stays the same.

A 1920 × 1080 picture reaches 3840 × 2160 at 2×, and a 960 × 540 one at 4×. A 1600 × 1200 picture becomes 3840 × 2880. The 4K choice is only shown when it is possible for your picture: below 960 pixels on the long side, 4× is as far as the tool goes.

Tips

The shape of your picture is kept, so it is not cut to 16:9. If it is not 16:9, a wallpaper will show bars or be cropped by your screen, not by this tool.

For a wallpaper or a slide, start from the biggest version you have. A picture already at 1920 × 1080 or more needs only 2× or less, so it looks much better than one that has to be made 4×.

Save as JPG for a smaller file, or PNG for the best quality. A 4K picture is 8.3 megapixels, so the file is large. You can ask for it to stay under a size.

Questions and answers

What size is 4K?

The 4K used by TVs and monitors (UHD) is 3840 × 2160 pixels, which is 8,294,400 pixels. Cinema 4K is 4096 × 2160. This page aims for a long side of 3840 pixels.

Can I make 8K?

No. 8K is 7680 × 4320 pixels, about 33 million, and the tool stops at 16,777,216 pixels. The limit is the same on every device and was chosen to suit phones.

My picture is already bigger than 3840 pixels. What happens?

There is nothing to enlarge to 4K. The tool offers the biggest step that fits in its limit, which for a picture that size is well under 2×, or tells you the picture is already at the limit.