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🖼️ Image & Photo Tools

Pack Local Images into a Sprite Sheet and Export CSS Coordinates

Create a deterministic grid atlas from real image files and retain frame metadata.

Reviewable output

Processed

Warnings / conflicts

Output state

Up to 50 PNG, JPEG or WebP files, 10 MB each and 40 megapixels total. Files stay in this browser tab.

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How the calculation works

Local inputboundedPer-item ruledeterministicArtifactcopy / download

How to Use This Tool

Create a deterministic grid atlas from real image files and retain frame metadata. Pack multiple local images into a sprite sheet, calculate padded frame coordinates, preview the atlas, export CSS positions, and download PNG locally.

The work this page finishes

Combining icons manually loses exact source names and background offsets; a useful sprite workflow must output both the bitmap and deterministic frame coordinates. For Sprite Sheet Maker, a visible row-by-row result preserves provenance, making a single correction possible without rerunning unrelated records or uploading the batch.

Rows or choicesValidate every itemReview and export
Four differently sized frames in two columns produce a two-row atlas and a stable coordinate record for every filename.

Deterministic workflow

Find the largest decoded frame, create a padded fixed-size cell grid in source order and derive each image's top-left coordinate and negative CSS background position. For Sprite Sheet Maker, input guards stop after 5,000 records or 2 MB, and the report separates fatal input problems from recoverable row warnings.

Why a dedicated interface helps

Download the PNG and coordinate CSV together, then reference the reported offsets in CSS or convert the manifest for the target engine. For Sprite Sheet Maker, deterministic ordering, one-click copying and a downloadable artifact make repeated operational review easier than manually reconstructing a response from prose.

Assumptions

  • Source order is meaningful.
  • Images retain original pixel dimensions.
  • Transparent padding is acceptable.

For Sprite Sheet Maker, do not discard the source after export: compare the destination result with it, and remember that local execution cannot secure the surrounding device or browser add-ons.

Limitations and review boundary

Fixed cells prioritize reproducibility over optimal packing and do not trim transparency, rotate frames, extrude edges or emit engine-specific atlas formats. For Sprite Sheet Maker, user values are never run as script, rendered as markup or fetched as network destinations; the page writes them only into text nodes.

Verification and provenance

On 2026-08-26, the rule and examples were cross-checked with MDN — Canvas API, including a known result, a rejected input and a conflict or duplicate case. Four differently sized frames in two columns produce a two-row atlas and a stable coordinate record for every filename.

Sources & assumptions

Tool Spec v2 · verified 2026-08-26. Platform rules and fees can change; the editable inputs remain authoritative for your account.

Official references

Model assumptions

  • Source order is meaningful.
  • Images retain original pixel dimensions.
  • Transparent padding is acceptable.
  • Fixed cells prioritize reproducibility over optimal packing and do not trim transparency, rotate frames, extrude edges or emit engine-specific atlas formats.
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Frequently Asked Questions

What does Sprite Sheet Maker complete?
It applies the stated generator rule to sprite sheet maker inputs and produces the reviewable output shown above.
Why use a dedicated Sprite Sheet Maker page instead of chat?
The Sprite Sheet Maker workflow preserves ordering, applies identical validation on every run and creates an artifact without conversational drift.
Does Sprite Sheet Maker send the input to ecech?
No. Sprite Sheet Maker reads pasted or selected content inside the current browser tab and does not call an ecech calculation API.
What verifies the default result?
Four differently sized frames in two columns produce a two-row atlas and a stable coordinate record for every filename.
When should I reject the output?
Fixed cells prioritize reproducibility over optimal packing and do not trim transparency, rotate frames, extrude edges or emit engine-specific atlas formats.
Which reference supports Sprite Sheet Maker?
The recorded Sprite Sheet Maker reference is MDN — Canvas API, reviewed 2026-08-26.

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