Create frame-by-frame animations from sprite sheets using CSS steps() timing function.
CSS Sprite Animation Tool converts sprite-sheet frame settings into CSS that exposes one frame at a time. It combines a frame-sized element, a moving background position, keyframes, and the CSS steps() timing function so the browser jumps between cells instead of tweening through the artwork. The most common surprise is that frame count alone is not enough: the visible box, each cell's dimensions, the movement distance, and the step count must agree, or the animation can reveal adjacent or empty areas.
The visible element acts as a window onto the sprite sheet. Across the animation's keyframes, its background position shifts through the frame cells. Because steps() makes the timing discrete, the browser holds one background position and then jumps to the next instead of displaying intermediate positions that would expose parts of neighboring frames.
The animation duration applies to one complete pass through the configured sequence. When the number of timing steps matches the frame sequence, each frame receives an equal share of that duration. Repeating the animation restarts the sequence after the final interval, so the first and last frames should be chosen with the loop transition in mind.
The movement endpoint may advance beyond the final valid cell, or the visible element may not match the sheet's cell dimensions. Check the sheet width and height, the number of equal cells, the frame box, and the background-position distance. Padding or transparent space inside the source image can also look like a missing frame.
Not with one uniform steps()-driven background-position sweep. That technique assumes predictable frame offsets and equal timing intervals. An irregular atlas needs explicit positions and may also require per-frame dimensions or origin data. Repack the artwork into equal cells before using this tool, or write individual keyframes for the atlas.
The behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.
Format, validate, and beautify JSON with syntax highlighting and error detection.
Encode text or files to Base64 and decode Base64 strings back to their original form.
Format and indent SQL queries for better readability across all major dialects.
Convert HTML markup into clean Markdown syntax with support for tables and lists.
Write Markdown and see the rendered HTML output in real time with live preview.
Visualize unified diffs and patch files with color-coded additions and deletions.