Threads Pinch-to-Merge Image Splitter
Split a tall photo or panorama into 2-10 carousel tiles that snap back together when viewers pinch on Threads. Runs in your browser, with built-in iPhone HEIC decoding.
Drag, drop, paste, or browse
JPG, PNG, WEBP, GIF, AVIF, and HEIC up to 50 MB. Paste from clipboard with Ctrl+V.
Threads pinch-to-merge splitter
No image selected - 2 side-by-side columns at 1080 x 1350 each
Upload an image to start splitting.
Useful to know
How pinch-to-merge works on Threads
When a Threads post contains 2 or 3 adjacent carousel images that line up edge-to-edge, viewers can pinch them to zoom out and see the merged composition as one large image. The gesture works best on 2-3 tiles - more is allowed in a carousel but the merge stops being clean. This tool slices a single source into 2-10 carousel-ready tiles so the pinch reveals your original image.
Vertical or horizontal?
Vertical (stacked rows) for tall portraits, screenshots, infographics, and anything that reads top-to-bottom - tile 01 is the top slice. Horizontal (side-by-side columns) for landscapes, panoramas, before/after pairs, and anything that reads left-to-right - tile 01 is the leftmost slice. Both export tiles at the same pixel resolution; only the cut direction changes.
4:5 vs 1:1 tile shape
4:5 (1080 x 1350) is Threads' tallest feed-friendly format and gives you the most vertical screen real estate per tile. 1:1 (1080 x 1080) is safer if you also plan to cross-post the same carousel to Instagram, X, or LinkedIn squares. Toggle freely - re-slicing with the other shape takes a second.
iPhone HEIC support
Drop a .heic or .heif straight from your iPhone Camera Roll, AirDrop, or Files app. ImgShifter decodes it locally with a WebAssembly module and the splitter sees a standard JPG, so the tiles you download are JPGs that Threads accepts as-is. No separate HEIC-to-JPG conversion step, and the HEIC decode never uploads to a server.
Privacy
Splitting runs entirely in your browser - Canvas API for the slice, JSZip for the bundle, WebAssembly for HEIC decode. Your image never reaches an ImgShifter server. Verify it: open DevTools Network tab while you slice (zero outbound image traffic) or disconnect from the internet after the page loads (the tool keeps working).
Threads Image Splitter online with ImgShifter
The Threads Image Splitter cuts one photo into 2-10 carousel tiles that line up edge-to-edge, so viewers can pinch any two or three adjacent tiles inside a Threads post to merge them back into the original image. Pick vertical (stacked rows) for tall portraits and screenshots, or horizontal (side-by-side columns) for landscapes and panoramas, and choose 4:5 (1080 x 1350) or 1:1 (1080 x 1080) per tile.
iPhone HEIC and HEIF files are decoded on-device via a WebAssembly module before slicing, so a .heic from your Camera Roll drops in directly with no separate conversion step. JPG, PNG, WEBP, and AVIF are also accepted. Tiles are exported as JPG, which Threads accepts without complaint.
Forward numbering keeps posting simple: imgshifter-threads-01.jpg is the first tile in the carousel (top for vertical, leftmost for horizontal), and the highest number is the last. Add them to a Threads post in numerical order, publish, and the pinch gesture handles the rest. Nothing leaves your device - the Canvas slice and JSZip bundle both happen in your browser.
Related tools
Other ImgShifter tools people use alongside Threads Image Splitter.
Instagram Carousel Splitter
Split one wide or tall photo into Instagram carousel slides that line up edge-to-edge. Viewers swipe through to reveal the full image. Browser-only, with iPhone HEIC support.
Image Splitter
Free online image splitter. Cut any photo into 2-10 equal parts horizontally or vertically - source-aspect, 4:5, 1:1, or 16:9 tiles. Runs in your browser, no upload.
Instagram Grid Maker
Split one photo into a multi-tile Instagram grid (3x1, 3x3, 3x6 puzzle feeds and more). Each tile exports at 1080 x 1350 with reverse-ordered filenames so the grid resolves perfectly when posted.
Crop for Instagram
Crop photos to Instagram's square (1:1), portrait (4:5), grid-perfect (3:4), and story or reel (9:16) ratios right in your browser.
Frequently asked questions
Short answers for image workflows, privacy, and supported formats.