OneTaskBy Tim King · Updated
Combine Images
Put Two Pictures Side by Side or Stack Them Vertically in One PNG
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How the Combine Images works
Combine images into one picture: drop in two or more photos and join them side by side or stack them top to bottom. Handy for before and after shots, comparison screenshots and long vertical strips of receipts or chat messages.
How to combine images
Click the file picker and select every image you want to join; hold Ctrl or Cmd to pick several at once. They are placed in the order your system hands them over, which is usually alphabetical by file name, so rename them 1, 2, 3 if the order matters. Choose Side by side for a horizontal row or Stacked for a vertical column, and the preview shows the joined result straight away.
Matching sizes
Photos from different sources rarely share a size. With matching on, side-by-side images are scaled so they all have the height of the tallest one, and stacked images so they all have the width of the widest. That gives clean, straight edges, which is what you want for a before and after pair. Turn it off to keep every image at its original pixel size; smaller ones are then centred on the background colour.
Gap, edge and background
The gap slider adds the same space between images and around the outside, filled with the background colour. A white gap of 10 to 20 px gives a tidy collage look; a black one suits photos with dark edges. Leave it at 0 for a seamless join.
Very large results
Browsers cannot draw a canvas over 16384 px on a side, so if several large photos would exceed that, the whole result is scaled down proportionally to fit and a note says so. The output is always a lossless PNG.
Private by design
Every image is decoded and joined inside your browser. Nothing is uploaded, and EXIF metadata from the originals does not carry over to the combined file.
FAQ
How do I put two pictures side by side?
Select both images at once in the file picker, leave Layout on Side by side and download the result. With matching on, both are scaled to the same height so the joined picture has straight edges.
How do I control the order of the images?
Images are placed in the order the browser receives them, usually alphabetical by file name. Rename the files with leading numbers such as 1-before and 2-after to fix the order you want.
Can I stack screenshots into one long image?
Yes. Choose Stacked and select all the screenshots. With matching on, each is scaled to the same width, which keeps long chat or receipt strips neat and readable from top to bottom.
Why is my combined image smaller than expected?
Browsers cap a canvas at 16384 pixels on each side. When the joined result would exceed that, it is scaled down proportionally to fit, and the tool shows a note telling you it has done so.
See also: all Images tools, Audio, Video & Screen, PDF, SVG, Simulations & Screensavers, Generative Art, Chart Makers, 3D Model Viewers, Drawing Pads, Mockups & 3D Making, Diagram Makers, 3D Science, Tracker Music.
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