Merge images
Combine two or more images into a single photo: side by side, stacked, or in a grid. Everything runs in your browser, the files never leave your device.
JPG, PNG or WebP, you can pick more than one
When merging images helps
A before/after comparison, a collage of memories, two screenshots to show together, a strip of photos for a story: merging images into a single file makes everything easier to share and upload to social media.
Stacked, side by side, or grid?
With stacked the images are placed one below the other and aligned to the same width; with side by side they line up at the same height; the grid arranges them in a square block, handy when you have many photos.
The three arrangements, and when to use them
Stacked is the choice for a vertical before and after, for a conversation cropped from a screen or for a step-by-step recipe: the images are brought to the same width, so it helps if they start with similar proportions. Side by side is the choice for comparison, because the eye compares what sits on the same line.
Grid is for when there are many images and none is more important than the others: a collage, a collection, a product sheet. Above six or eight images, though, each becomes too small to say anything: better two separate files than one illegible grid.
The problem of different proportions
If the images have different shapes, joining brings them to a common size and something has to give: either you crop, losing the edges, or you stretch, and on a face or a logo it shows immediately. The third route is adding coloured bars, which is the correct choice when the images are charts or documents and cropping would mean losing information.
The way to avoid the problem is cropping each image first to the same proportions, rather than letting the join decide. On a before and after in particular, the two photos must share the same framing: a comparison in which the framing changes proves nothing.
What makes a before and after work
Three things, and none of them is the editing: the same distance, the same light and the same viewpoint. A comparison where the second photo is taken closer or in better light looks rigged even when it is not, and that is why advertising comparisons are recognisable at a glance.
It is worth adding a small gap between the two images: without a separation the eye reads them as a single photo and the comparison is lost. A white line a few pixels wide is enough, and adding «before» and «after» labels removes any ambiguity about the order.
Size, and the right format
A joined image weighs as much as the sum of its parts, and with four phone photos you easily reach several megabytes. So it is better to resize first and compress at the end, once only: the result is lighter and the quality better than compressing each piece and then joining.
On format the rule is the usual one: JPEG if the images are photographs, PNG if they contain text or screenshots, where the sharp edges of letters take compression badly. A collage of screenshots saved as JPEG becomes illegible far sooner than expected.
Nearby tools
To prepare the images there are Resize photo and Compress image, to add labels Write on a photo. To make a document out of them there is Image to PDF, and to cover a detail Blur part of a photo.