Merge Images

Side by side places the pictures in one row from left to right. It is the layout for before-and-after comparisons, two versions of a design, or a product shown from two angles. With Match sizes on Auto, every picture is given the same height, so the tops and bottoms line up and the row looks like one piece.

Stacked places them in one column from top to bottom. It joins screenshots of a long conversation or web page into a single image, turns a set of slides into one tall picture for a phone screen, or puts a recipe's steps one under the other. In this layout Auto gives every picture the same width.

Grid arranges the pictures in rows with the number of Columns you set, from 1 to 10; new rows are added as needed, so nine pictures in three columns make a 3 × 3 grid and seven pictures in three columns leave two empty cells at the end. Every cell has the same size. Grid cells decides how a picture fills its cell: Fill cell crops it so the grid has no gaps, and Fit whole image shows the entire picture with background around it. Fill gives the tidy collage look; fit is safer when nothing may be cut off, such as documents or artwork.

Whatever the layout, the order of the file list is the order of the pictures: left to right, top to bottom, and row by row in a grid. Move files up or down in the list, or set Order to File name or Date taken to sort them automatically.

A grid works for more than social collages. Product photographers use it for a catalog overview, teachers for a sheet of worksheet answers, and families for a single picture that holds a whole trip. Three or four columns usually read best on a phone screen; more columns make each picture small, which is fine for a contact sheet but not for a post.

By default the pictures sit edge to edge with no space and no frame. That is often right for a panorama assembled from parts, or for screenshots that should read as one continuous page. For collages and comparisons, a little space usually looks better, because it separates the pictures and stops their colors from running into each other. The settings below shape the space around and between the pictures; each one is measured in pixels of the finished image.

A white background with a small gap and border suits printed collages and anything placed on a white page. A black background makes photos look richer on screen and hides small differences in their edges. A custom color can match a brand or a slide template, so the collage drops into a presentation without a visible box around it. Rounded corners combine well with a gap; without a gap, the rounded corners of neighboring pictures leave small background-colored notches where they meet.

Photos from different phones, screenshots from different devices and pictures saved from the web rarely share the same dimensions. Match sizes decides how they are brought together. Auto is the default and gives every picture the same height in a row, the same width in a column, and the same cell in a grid. It is what most people want, because it makes the layout line up without any work.

Smallest matches every picture to the smallest one, so no picture is enlarged and nothing turns soft; the result is lighter but may be smaller than you hoped. Largest matches every picture to the largest one, which keeps the biggest picture at full detail and enlarges the others. Keep original leaves every picture at its own size and aligns them as they are, with background filling the space; it is useful when the sizes themselves carry meaning, such as icons shown at their real pixel size.

Shapes matter as much as sizes. A portrait photo next to a landscape one will never line up perfectly in a row: with the same height, the landscape picture is much wider. If the pictures should look like a matched pair, crop them to the same shape first with the Crop Image tool, for example both to 1:1 or both to 4:5, and then merge them.

Resolution differences show most in a grid. If one picture in a set is much smaller than the rest, Auto and Largest have to enlarge it to fill its cell, and it will look softer than its neighbors. Replacing it with a larger copy is the best fix. If none exists, Smallest brings every picture down to its level, so the grid looks even, if smaller overall.

Output format starts on JPG, which keeps a collage of photos reasonably light and opens everywhere. Choose PNG for screenshots, diagrams and anything with text, since PNG keeps sharp edges without compression artifacts, and also for transparent backgrounds. WebP keeps transparency in a smaller file for websites. PDF turns the merged image into a single-page document, which suits a set of receipts or ID scans that must be sent as one file.

Screenshots of chats and accounts often show names, phone numbers or email addresses. Before merging them into an image you will share, hide those details with the blur or pixelate effect in Image Effects. Doing it before the merge is easier than after, because each screenshot is still a separate file and you can treat only the ones that need it.

Quality applies to JPG, WebP and photos inside a PDF and starts at 85, which keeps photos visually identical to the originals. The finished image can still be heavy, because it holds the pixels of every picture combined. If it is meant for a site with an upload limit, lower Max width first; that reduces the pixel count, which matters far more than the quality setting. For a strict KB limit, run the result through the Compress Image tool afterwards.