Combine images into one

Which layout fits your pictures

Side by side joins images horizontally, in one row, and suits two to four pictures: a before and after, two versions of a design, or two photos you want to compare. Stacked joins them vertically, one above the other, for screenshots of a long chat or web page, receipts, and anything people read from top to bottom. A grid suits four, six or nine photos of one trip or product. Only have one portrait photo? Make a single portrait photo landscape by adding new sides instead.

With Same height, every picture in a row is scaled to the shortest one, so their tops and bottoms line up and nothing gets enlarged. As they are keeps each picture at its own pixels and lines the smaller ones up at the top, middle or bottom. Grid cells all take the shape of image 1. Pictures with another shape either fit inside their cell with the background around them, or are trimmed from the middle to fill it. When one picture is much smaller than the rest, the tool names it, because it sets the size of all the others.

Quality, formats and file size

PNG keeps every pixel exactly, which suits screenshots and text, but photos make large PNG files. JPG and WebP are far smaller for photos. In our test, two landscape photos side by side, 2,400 x 675 pixels, came to 2.18 MB as PNG, 337.2 KB as JPG and 199.4 KB as WebP at quality 92. Like our other size tools, it counts 1 KB as 1,000 bytes.

Combined phone photos get big quickly, since four photos side by side are four photos wide. Browsers cannot draw pictures of any size, so the tool keeps the result under about 16 million pixels and tells you when it scaled it down to fit.

Tick Keep the file under a size for upload forms and email. The tool then looks for the highest JPG or WebP quality that fits, with the same method as our compress to KB tool. With Set width or Exact size it keeps your pixels and changes only the quality. At Full size it makes the picture smaller only when quality alone cannot get there, or when the quality would drop below 50, where a slightly smaller picture looks better. It then shows the new size.

In our test, four photos in a two by two grid, fitted into a 1080 x 1080 square with white above and below, came to 159.3 KB as a JPG at quality 92. With a 100 KB limit the tool kept 1080 x 1080 and saved at quality 80, at 97.1 KB. Three photos side by side, 3,033 x 1,167 pixels, fitted under 500 KB at quality 75 with every pixel kept. Under 300 KB they would have needed quality 45, so the tool saved them at 2,639 x 1,015 pixels and quality 66 instead.

Exact sizes, spacing and transparency

Set width gives the combined picture a fixed width, such as 1080 pixels, and the height follows its shape. Exact size fits it inside a width and height you choose, centered, with the background color filling any space left over. The spacing stays the number of pixels you set, whatever the output size, so a 20 pixel gap is 20 pixels in the file.

Choose Transparent for a PNG or WebP with see-through gaps, ready to place on a slide or a web page. JPG cannot store transparency, so a JPG gets a white background there. With a size limit on, Transparent saves as WebP, since a limit always saves as JPG or WebP. Some browsers cannot save WebP: the tool then says so and saves a PNG instead, or a JPG under a size limit. WebP has a ceiling of its own: Google's WebP FAQ gives 16,383 x 16,383 pixels as the largest WebP image, so a longer strip than that needs JPG or PNG.

Built-in ways on phones and computers

Most devices can make a simple version of this. In the table, the first three rows and their limits come from each maker's own help page. The Windows row is the usual way round it in Paint, which has no combine command. This page adds what those leave out for forms and posts: an exact pixel size, a KB limit and transparent gaps, for up to nine images in the order you choose.