Updated October 2026
In a standard multi-photo carousel, the first slide is usually a deliberately chosen "cover" image. In a seamless carousel — where every slide is an equal slice of one continuous image — the first slide is whatever your source image's leftmost section happens to be, which means getting it right requires thinking about composition differently.
It has to work as a standalone thumbnail (the only part of your post visible before anyone swipes, and the part shown — center-cropped to a square — in your profile grid) and as the starting slice of the wider composition. A first slide that looks confusing or incomplete on its own can reduce how many people bother to swipe further, even if slides 2 onward are the most interesting part.
If you have control over the source photo or illustration's composition, consider deliberately placing a clear focal point, a readable piece of text, or a recognizable subject within roughly the leftmost 1/N of the frame (where N is your planned slide count) — that's the section this tool will cut into slide 1. For a photo you can't recompose (an existing panorama, for instance), check this tool's live preview and consider adjusting slide count specifically to change where the first boundary falls, landing a stronger subject within slide 1.
Wide images often have less visually interesting content at their extreme edges (empty sky, a plain wall, out-of-focus background) compared to the center. If your first slide lands on one of these low-content edges, viewers have less reason to swipe. Where possible, frame or crop your source image before uploading so the leftmost section isn't the emptiest part of the composition.
If you're adding text overlays after exporting (in a design tool, since this tool itself doesn't add text), keep in mind the grid-preview square crop will cut off the top and bottom portions of a Portrait slide — place any critical text within the central square-safe area if you want it visible in both the grid thumbnail and the full opened post.
Use this tool's live preview grid to review all generated slides together before downloading — it's much easier to spot a weak first slide or an awkwardly-placed subject at this stage than after the carousel is already posted.