Horizontal join with top alignment
Input and settings
Red 2×1 px followed by blue 1×2 px; horizontal, Start alignment.
Expected result
3×2 px: red/red/blue on top, transparent/transparent/blue below. Source images are not enlarged.
Image Joiner
Join JPEG, PNG and WebP images horizontally or vertically at their original display dimensions. Reorder and align images, then save a PNG with transparent padding.
How to use
- Choose the images together and reorder them with Up and Down.
- Choose the joining direction and alignment for different image sizes.
- Join and save PNG, then inspect order and alignment.
Images and joining settings
Drop 2 to 20 images here. A new selection replaces the list.
JPEG, PNG or WebP; 2–20 images, at most 40 MB each and 80 MB combined. Inputs and output: 70 megapixels and 16,384 px per edge. PNG output: 96 MB. Memory estimates may reject otherwise valid sizes. No reduced-size export is made.
Selected images (joined in this order)
Joined image
Try a use case and check the result
Inspect transparent padding when joining unequal images without resizing.
Example buttons replace the inputs and settings above and calculate. Restore previous input steps back one example at a time. After trying multiple examples, repeat restore to return to your original input. This history is lost when the page closes.
Vertical join with right alignment
Input and settings
The same order; vertical, End alignment.
Expected result
2×3 px: red/red on top, then two rows of transparent/blue.
How to read the result
Start/End mean top/bottom for horizontal joins and left/right for vertical joins. Images retain their display dimensions; unused space stays transparent. Reordering changes export placement.
Scope and limits
2–20 JPEG/PNG/WebP images, 40 MB each and 80 MB combined (decimal). Output: 70 megapixels, 16,384 px per edge and 96 MB. Estimated-memory limits may apply sooner. Only the preview is reduced; limit failures do not silently produce smaller exports.
Calculate placement and padding independently; validate every exported pixel, dimensions, original order and settings.
Continue with the next task
Details and limits
Choose 2 to 20 images together and reorder them with Up and Down. Horizontal joining runs left to right; vertical joining runs top to bottom. A new selection replaces the list. Remove deletes an image from the list.
Images use their browser-decoded display orientation and dimensions. They are not resized or cropped. Horizontal output sums widths and uses the greatest height; vertical output sums heights and uses the greatest width.
Different sizes align to start, center or end. Unused areas stay transparent, with no gaps between images. Odd center padding has one fewer pixel on the left or top.
For images 3×2 px and 2×3 px, horizontal output is 5×3 px and vertical output is 3×5 px.
Only the preview is reduced to a maximum edge of 1,200 px. The saved PNG uses the original display dimensions; its width and height appear in the result. This differs from a contact sheet that fits images to paper.
PNG rendering does not guarantee complete preservation of original colors or metadata. Animation is not retained. Original files are unchanged.
Encoded size, declared dimensions and combined dimensions are checked before decoding. Estimated output buffers and the largest input use a 256 MB budget on limited-memory devices and 1 GB otherwise. Browser internals vary, so decoding may fail within the declared limits. Try fewer or smaller images.
Changing files, direction, alignment or order clears old output. Cancel keeps the list; reset clears images and output, keeping settings. A native browser operation may need to finish before cleanup, but delayed results are discarded and cannot be saved.
Processing stays in your browser. Images, output and filenames are neither stored nor sent. SVG, GIF and HEIC are not supported.
Frequently asked questions
Does saving preserve pixel dimensions?
Yes. Browser-decoded display dimensions are kept without resizing. Only the preview is reduced.
What if the images have different sizes?
They align to start, center or end with transparent padding. No cropping or resizing to a common size is performed.
What if large images cannot be processed?
Use fewer or smaller images. Dimension, byte and estimated memory limits reject oversized work instead of silently reducing saved dimensions.
Related tools
Share this tool
Share only the tool name and public URL. Your input and results are not included.
Inputs and storage
Keep any content you need before clearing. This tool does not autosave inputs or results. Reloading or closing the page, clearing inputs or resetting may discard your work.
Favorites and language preferences are stored separately and may be lost when site data is cleared. Tool resets and site-data deletion do not delete files already downloaded to your device.