What this tool does
This is a free browser tool that slices a single image into Instagram-ready pieces. Three modes cover the three things people actually want from a "carousel splitter": a vertical swipe carousel made from a tall image, a horizontal seamless feed where one panorama spans multiple square posts, and the legacy 3-column profile mosaic where many small squares assemble into one big image on your feed grid.
All slicing happens in your browser via the HTML Canvas API. The image never leaves your device, there's no compression beyond what PNG gives you, and the export resolution is whatever your source image was. If you upload a 6000×8000 photograph, you get 6000×8000 pixels of total output across the slides.
How the three modes work
Vertical carousel
Best for infographics, recipe steps, threads, or any tall artwork meant to be read as a single image as you swipe. Pick the slide count (2 to 10), pick the per-slide aspect ratio (1:1 or 4:5), and the tool slices vertically. Each slide exports at the slide's full pixel dimensions so it stays sharp on Retina screens.
Horizontal seamless feed
Best for panoramas that flow continuously across multiple square posts. Drop a wide image, pick 2 to 10 slides, and the tool slices horizontally into squares. When followers swipe your carousel, the image reads as one continuous panorama instead of disconnected crops.
Profile grid mosaic (3 × N)
The classic Instagram "puzzle profile" effect. Your tall artwork is sliced into a 3-column grid with N rows. The export is automatically numbered so that posting in numeric order lays the mosaic out correctly on your profile feed, bottom-right first, top-left last.
Smart fit and interactive crop
If your image's aspect ratio already matches the chosen layout, the tool tells you and locks the framing. If not, you pan and zoom the image inside the grid frame to pick what's visible in each cell. The cell outlines stay locked, so you can see exactly how the export will look before you download.
Zero quality loss
The tool reads your image at its native resolution and writes lossless PNGs. There is no JPEG re-encoding step, no downscale, no smoothing pass. The only transformation is the canvas crop, which is bit-exact for the visible region.
Frequently asked questions
How do I post the mosaic so it lines up on my profile?
Post the exported files in numeric order. The tool numbers them so the first file (01) is the post that lands at the bottom-right of your profile grid, and the last file (N) lands at the top-left. Posting in this order is required because Instagram puts the newest post at the top-left of the grid and works rightward and downward.
What's the best slide count for vertical carousels?
Three to five slides reads best on mobile. Two slides feels short. More than seven is usually scrolled past. The tool supports up to ten.
Does Instagram compress my images after upload?
Yes, Instagram always re-encodes on upload. The tool gives you the highest-quality starting point so the re-encoded result is as clean as possible. Uploading PNGs sized at 1080px wide (or 2160px for 2x retina) gives the best results in our testing.
Why is my image getting cropped?
The chosen layout's aspect ratio doesn't match your source image. Use the zoom slider and drag the image inside the canvas to pick what shows. Or change the mode or slide count so the grid aspect matches your source.
Is it really lossless?
Yes for the splitter output. The canvas reads source pixels and writes PNG with no quantization. Once uploaded to Instagram, their server-side recompression applies, which is outside any client tool's control.
Does it work on mobile?
Yes. The interface is touch-first, the canvas supports pinch zoom and drag, and the export is the same client-side ZIP. On iOS Safari, the ZIP saves to Files.