What is an image combiner?
An image combiner takes two or more separate picture files and draws them into one new picture. Side by side in a row, stacked top to bottom, or laid out in a grid. What comes back is a single PNG or JPG that behaves like any other image — attach it, paste it, upload it, print it.
People need this constantly and almost never for anything fancy. Two screenshots that have to travel together in a bug report. A before-and-after pair for a listing. The phone version of a page next to the desktop version. Four product photos for a marketplace that allows exactly one image. A receipt and its envelope merged into one file for an expense claim. The job takes five seconds of actual work, and the usual route to it is opening a design suite, signing into an account, picking a template you don't want, and exporting past a watermark.
The Image Combiner on this page takes 2 to 10 files — PNG, JPG, WebP, GIF, BMP, or HEIC from an iPhone — arranges them the way you pick, and hands back one file. The drawing happens on a canvas inside your browser, so the pictures never leave your device. Open the Network tab in your browser's developer tools while you use it: nothing carrying your images goes out.
How to combine images in your browser
Using the image combiner is five steps, and two of them are optional.
- Add your images. Drop them on the box, click it to pick them, or paste straight from the clipboard with Ctrl+V (Cmd+V on a Mac). Two to ten files, up to 20 MB each.
- Put them in order. Each image gets a row with a thumbnail, its filename, and its pixel size. The arrow buttons move it earlier or later; the × removes it. The order in that strip is the order in the output.
- Pick a layout. Side by side, Stacked, or Grid. The preview redraws immediately — there's no Combine button to find, because the preview is the result.
- Adjust if you want to. A gap slider from 0 to 100 px puts space between the images. A colour picker fills that space and any padding; transparent is the default. Choose PNG to keep transparency or JPG for a smaller file.
- Download. The file saves as
combined-image.pngorcombined-image.jpg. Copy image puts it on your clipboard instead, ready to paste into a chat or a document.
The paste shortcut is the fastest path on a laptop. Take a screenshot with Shift+Cmd+4 or the Windows snipping tool, press Ctrl+V on this page, take the second one, paste again — both images are in and the preview is already drawn. No file dialog, no Downloads folder.
Three layouts, and when each one is right
| Layout | Arrangement | Output shape | Best for |
|---|---|---|---|
| Side by side | Left to right, in your order | Wide | Before and after, two phone screenshots, a comparison |
| Stacked | Top to bottom | Tall | A long chat thread, numbered steps, a scrolling page in parts |
| Grid | Rows and columns, filled left to right | Roughly square | Product photos, thumbnail sheets, four of anything |
The grid picks its own column count: the square root of the number of images, rounded up. Four images become 2 columns and 2 rows. Five through nine become 3 columns. Ten becomes 4 columns across 3 rows, with the last row partly filled. That rule produces the closest thing to a square every time, which is what almost everyone wants from a grid and what reads best in a message thread.
A worked example: two screenshots into one file
Say you have a desktop screenshot at 1920 × 1080 px and a phone screenshot at 1170 × 2532 px — a standard iPhone capture. Same page, two devices, one bug report. Here is what each setting actually produces, in real pixels:
| Images in | Layout | Sizes | Gap | Output |
|---|---|---|---|---|
| 2 × 1170 × 2532 | Side by side | Match them up | 0 px | 2340 × 2532 px |
| 1920 × 1080 + 1170 × 2532 | Side by side | Match them up | 0 px | 2419 × 1080 px |
| 1920 × 1080 + 1170 × 2532 | Side by side | Keep original | 0 px | 3090 × 2532 px |
| 4 × 1080 × 1080 | Grid | Match them up | 12 px | 2172 × 2172 px |
| 3 × 1200 × 800 | Stacked | Match them up | 16 px | 1200 × 2432 px |
Read the second row closely, because it's the one that surprises people. Matching two images of wildly different shapes brings the tall phone screenshot down to the desktop screenshot's height of 1080 px, which makes it 499 px wide. Total width: 1920 + 499 = 2419. The third row is the same pair with nothing scaled — both images at their native pixels, the shorter one centred in a 2532 px-tall canvas with the background filling the space above and below it.
Notice the fourth row too. Four 1080 px squares with a 12 px gap come to 2172 px, not 2184: gaps go between images and never around the outside edge. One gap between two columns, one between two rows. 1080 + 12 + 1080 = 2172.
Match them up or keep original
Two size modes cover nearly everything.
Match them up
Every image is scaled so the shared edge is identical — equal heights in a row, equal widths in a column, equal cells in a grid. You get a clean join with no padding anywhere, and the result reads as one picture rather than a collage.
It always scales toward the smallest image, never the largest. Combine a 100 × 100 thumbnail with a 200 × 200 photo and you get 200 × 100 px: the big one comes down to meet the small one. That's a deliberate call. Blowing a 200 px thumbnail up to 4000 px doesn't recover detail that was never captured — it produces a soft, blocky patch sitting next to a sharp photo, and no setting afterwards undoes it. Shrinking the sharp one keeps both halves sharp.
Keep original
Nothing is scaled. Each image keeps its own pixels and the shorter ones are padded with your background colour. An align control appears and decides whether the padded image sits at the top, the middle, or the bottom of its slot. Use this when the pixel dimensions matter — a screenshot someone will zoom into, a scan that has to stay at 300 DPI, artwork you'll cut apart again later.
If you're combining images that started out at wildly different sizes and neither mode looks right, the fix is usually upstream: run them through the image resizer to a common width first, then combine. Matching the inputs beats fighting the output.
Where combining images goes wrong
Every one of these has a specific cause and a specific fix, and most image combiners fail silently at least one of them.
The output comes out blank
Browsers stop painting a canvas somewhere around 16,000 pixels on a side, and mobile Safari is the strictest — it returns solid white rather than an error, which is why some merge tools quietly hand you an empty file. Ten 2000 × 2000 photos in a row would want 20,000 × 2000 px. Here, that gets scaled down proportionally to 16,000 × 1600 px and you're told it happened, in those words, above the Download button. If you need the full resolution, combine in two passes or stack instead of sitting them in a row.
Transparent areas turn black
JPG has no alpha channel, so transparency can't survive the format. The common bug is that transparent pixels are written as black, which wrecks a logo or a screenshot with rounded corners. A transparent background here is flattened onto white when you pick JPG, or onto whatever colour you chose. To keep the transparency, stay on PNG — which is the default for exactly this reason.
A phone photo lies on its side
Phones often store a photo in its sensor orientation plus a tag telling the viewer to rotate it. Tools that ignore the tag produce a combined image with one photo lying flat. Every image here is decoded with its orientation applied, so the preview matches what you see in your gallery.
Something in the batch isn't an image
Drop a folder and you'll catch a stray PDF or a .txt eventually. That file is skipped by name and everything else combines normally — losing the whole selection over one bad file would be a rude way to treat a drag and drop. Animated GIFs are accepted as their first frame, and the tool says so rather than letting you wonder where the motion went.
What this isn't
This is one job done fully: several images in, one image out. It isn't a photo editor. There's no crop, no rotate, no filter, no text layer, no sticker, no saved project. That's not a trimmed-down version of something bigger — it's the whole tool, and the missing features are missing on purpose. The moment an image combiner grows an editor it becomes the thing you were trying to avoid when you went looking for one.
The pieces that would be an editor already exist as their own pages: the image cropper for trimming, the image compressor when the combined file is too heavy for an email, the image format converter to change what you end up with, and the image to PDF converter when the destination wants a document rather than a picture. Each does one thing, each opens instantly, and none of them asks who you are.
That's the difference worth naming. The standard way to merge two pictures online is either a site that uploads your files to somebody's server and returns them with a watermark in the corner, or a full design platform behind an account, a per-seat price, and a trial clock that starts ticking over a thirty-second task. Both models are built around keeping you, not around finishing the job. This page has no account, no watermark, no export gate, and no daily limit — and it works the same whether you're a freelancer building a listing, a student assembling a lab report, or someone doing this on a work laptop at 2am.
Frequently asked questions
Can I combine images on my phone?
Yes. The page works on mobile browsers, and the file picker opens your camera roll, so you can select several photos straight from it. Two things to know on a phone: HEIC photos need a conversion step on the way in, which takes a moment and is signposted while it runs, and very large batches of full-resolution camera photos are the most likely to hit the canvas limit. If the output looks blank on an iPhone, that's what happened — the tool will have told you it scaled things down.
What size will the combined image be?
It's printed under the preview before you download, and it updates with every change you make. Roughly: side by side adds up the widths and takes one shared height; stacked adds up the heights and takes one shared width; grid multiplies the cell size by the columns and rows. Gaps are added between images only. Three 1200 × 800 images stacked with a 16 px gap come to 1200 × 2432 px — two gaps, not four.
Does combining reduce image quality?
In "keep original" mode with PNG output, no — every pixel is copied across unchanged. In "match them up" mode, images that get scaled down are resampled, which is a real but small quality change and usually invisible at the size you'll view it. Choosing JPG re-encodes everything at high quality and discards transparency. If you want the safest possible result, use keep original and save as PNG.
Is there a limit on how many times I can use the image combiner?
No. There's no daily cap, no account, no watermark, and no export gate — combine two images or two hundred pairs. Ten images per pass is the only ceiling, and you can feed a combined file straight back in to go past it. The tool is free to use, ads pay for the page, and 10% of every dollar Microapp earns goes to charity off the top, audited quarterly.
How do I put two images side by side without a design app?
This is the short answer to exactly that search. Open the page, drop both images, leave the layout on Side by side, click Download. If they're different heights, that's already handled — the default mode lines the heights up for you. If you'd rather they stayed at their own sizes with padding, switch Sizes to Keep original and choose where the shorter one sits.
Can I add a border or space between the images?
Space, yes — the gap slider goes up to 100 px, and setting a background colour makes that space visible rather than transparent. A white gap of 20 to 40 px is the usual choice for a comparison you'll post somewhere, because it stops the two pictures reading as one. An outer border isn't in this version. A working trick in the meantime: combine, then run the result through the tool a second time alongside a plain coloured image if you need a framing band on one side.
Do my images get uploaded anywhere?
No, and you don't have to take that on faith. The files are read from your device, decoded, drawn onto a canvas element, and handed back as a download. There's no server in the path. Open DevTools, switch to the Network tab, and combine a few images — no request carries your file. A pleasant side effect: once the page has loaded, the tool keeps working with the connection off entirely.