How to Merge Two Images Into One
Joining images sounds trivial until you try it and discover the two photos are different sizes, leaving one floating awkwardly next to the other. That is the actual problem this tool solves: not just placing images next to each other, but deciding sensibly what to do when they do not match. Choose a direction, choose how mismatched sizes are reconciled, and the rest is spacing.
Add your images
Two or more, in any format. Hover any of them to reorder or remove it.
Choose the layout
Side by side or stacked, then decide how differing sizes should be handled.
Set spacing and export
Add a gap, a margin and rounded corners if you want them, then download at full resolution.
Handling Images of Different Sizes
This is the decision that determines whether the result looks intentional. Match largestscales every image so they share the same height when side by side, or the same width when stacked. The edges line up cleanly, which is what you almost always want — the cost is that smaller images get scaled up, so a low-resolution one may look soft next to a sharp one.
Fit smallest does the reverse: it scales everything down to match the smallest image. Nothing is ever upscaled, so quality is preserved perfectly, but the whole result is limited by your weakest image. Use it when quality matters more than size, or when one image is dramatically larger than the rest.
Keep original sizes places each image at its natural dimensions, which produces a ragged edge unless the images happen to match. It has one genuinely good use: when the different sizes are the point, such as showing a mobile screenshot next to a desktop one at their true relative scale. In that case set the alignment to top or bottom so the ragged edge reads as deliberate rather than accidental.
Common Situations This Tool Solves
Before and after comparisons
Two images side by side with a small gap is the clearest way to show a change. Far more convincing than asking someone to swipe between two separate photos.
Combining screenshots into one attachment
Several screenshots of a bug or a workflow become one image, which arrives in the right order and cannot be viewed out of sequence.
Product shots from multiple angles
Merging three or four angles into a single image gives a marketplace listing one strong lead picture instead of several weak ones.
Stacking a long conversation or document
Vertical merging turns a series of scrolled screenshots into one continuous image that reads top to bottom.
Frequently Asked Questions
How do I merge two images into one for free?
Add your images, choose side by side or stacked, set the spacing, and download. Free, no signup and no watermark.
What if my images are different sizes?
Choose a sizing mode. Match largest scales everything to align cleanly, Fit smallest never upscales, and Keep original leaves them at natural size.
Can I merge more than two images?
Yes, as many as you like. They are placed in order, and you can reorder any of them by hovering and using the arrows.
Is my image uploaded to a server?
No. The merge happens on a canvas inside your browser. Your images are never uploaded, stored or seen by anyone.
How do I change the order?
Hover over any image in the preview and use the left and right arrow buttons to move it earlier or later in the sequence.
Can I have a transparent background?
Yes, choose the None background option and export as PNG. JPG cannot store transparency and will fill it with white.
Will merging reduce quality?
Only if an image is scaled up. Match largest may upscale smaller images, so use Fit smallest when preserving quality matters most.
What gap should I use?
Ten to twenty pixels reads as clean and deliberate. Zero creates a seamless join, which suits panoramas and continuous screenshots.
Can I merge images vertically?
Yes. Choose Stacked and they are joined top to bottom, which is ideal for long conversations or scrolled screenshots.
Which format should I download?
PNG for screenshots and graphics with sharp edges. JPG for photographs, where the file is far smaller with no visible difference.
Is there a limit on how many images?
No fixed limit, though very large merges use a lot of memory. The tool stops if the result would exceed practical canvas dimensions.
Is this image merger really free?
Completely free, with no limits, no watermark, no signup and no premium wall. Everything runs in your browser.
Last updated: July 20, 2026 · FlipMyFormat Image Merger
Written and maintained by the FlipMyFormat team