Should I slice by grid or by cell size?

Use By rows and columns when you know the layout — for example a 4 by 4 walk-cycle sheet — and the tool divides the sheet evenly into that many cells. Use By cell size when you know each frame is, say, 32 by 32 pixels but you are not sure how many fit; the tool figures out the column and row count from the sheet width and height. Both modes account for any outer margin and inter-cell spacing you enter.

What do margin and spacing do?

Margin is the blank border around the outside of the whole sheet before the first cell begins, set separately for the X and Y axes. Spacing is the gap between adjacent cells. Many exporters add a one or two pixel gutter to stop neighbouring frames bleeding into each other; set Spacing X and Spacing Y to that gutter width so each cell lands exactly on its art.

How does Trim transparent edges work?

With trimming on, the slicer scans each frame for fully transparent pixels around the edges and crops them away, leaving the tightest rectangle that still contains visible art. This is handy when you want frames sized to their content rather than to a uniform cell — for packing into another atlas, for instance. Frames that are entirely transparent are left at their full cell size. Trimming only affects formats with an alpha channel, so it has no effect on opaque JPGs.

What is in the downloaded ZIP?

The ZIP contains one PNG per selected frame, named from your pattern (frame_0.png, frame_1.png and so on), inside a folder named after your sheet. It also includes a frames.json manifest listing every frame name with its source x, y, width, height, row and column, plus the slice settings used. The manifest makes the cut reproducible and lets you re-import the coordinates into a game engine or build script.

Is my image uploaded anywhere?

No. The sheet is decoded and sliced entirely on your device using the browser canvas and the JSZip library running locally. Nothing is sent over the network, so you can safely cut unreleased game art, private icon sets or client assets.

Sprite Sheet Slicer — Gera Tools

Q: What is a sprite sheet slicer?

A sprite sheet slicer takes one large image that packs many smaller pictures — animation frames, tiles or icons — and cuts it back into separate image files. You tell it how the cells are laid out (a grid of rows and columns, or a fixed cell size in pixels) and it crops each region from the sheet into its own PNG. This tool runs the whole process on a canvas inside your browser, so a 256-frame sheet becomes 256 ready-to-use PNGs without any server round trip.

A sprite sheet slicer that turns one packed image back into individual frames. Upload a sheet, tell it how the cells are arranged — either a grid of rows and columns or a fixed cell size in pixels — and it crops every cell into its own PNG. You can exclude blank cells, trim transparent borders, name files with a pattern, and download everything as a single ZIP. It is built for game developers unpacking character animations, web developers extracting CSS sprite icons, and anyone who has a tile sheet but needs the tiles as separate files.

How it works

When you load a sheet the tool reads its exact pixel width and height, then computes a grid from your settings. In rows and columns mode it divides the usable area (sheet size minus any outer margin and inter-cell spacing) evenly into the number of cells you ask for. In cell size mode it instead works out how many whole cells of your chosen pixel dimensions fit across and down the sheet. Either way it accounts for margin (the blank border around the whole sheet) and spacing (the gutter between cells), so sheets exported with a one or two pixel gutter slice cleanly.

The live preview draws your sheet onto a canvas with the computed grid overlaid in blue. Click any cell to grey it out and drop it from the export — useful for the empty cells that pad the end of an animation row. Below the preview, a thumbnail of every frame is rendered so you can verify the cut before downloading. Each frame is drawn with image smoothing disabled so pixel art stays crisp at any zoom. When you export, each selected cell is redrawn at native resolution, optionally trimmed to its visible bounds, encoded as a PNG, and added to a ZIP alongside a frames.json manifest that records every frame’s coordinates and the exact settings used. Everything happens in the browser — no upload, no account, no watermark.

Example

Say you have a hero.png walk cycle that is 256 by 256 pixels containing a 4 by 4 grid of 64 by 64 frames. Choose By rows and columns, set columns to 4 and rows to 4, and the tool slices it into 16 frames of 64 by 64 each. If the last two cells of the bottom row are blank, click them in the preview to exclude them, leaving 14 frames. Set the name pattern to walk_{i0} for zero-padded names like walk_00.png through walk_13.png, then Download as ZIP.

Sheet	Mode	Settings	Result
256×256	rows × cols	4 × 4	16 frames of 64×64
512×64	cell size	64 × 64 px	8 frames in a strip
320×320, 1px gutter	cell size	32×32, spacing 1	tightly cut 32px tiles

Every frame is cropped in your browser — no pixels are ever uploaded or stored.