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Lottie Inspector

Inspect Lottie JSON runtime metadata, layer types, assets, compatibility features, and evidence-based delivery findings.

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Reviewed July 13, 2026

Guide, examples, and validation Show

About this tool

Inspect Lottie JSON before handing it to engineering or shipping it in a landing page. Check size, layer complexity, and asset usage from one screen.

Lottie Inspector is useful when teams need more than simple playback and want to inspect the structure of an animation asset. It helps with debugging layers, assets, markers, and metadata before the file moves deeper into product or motion workflows.

  • Reports source and minified bytes, canvas, duration, frame rate, frames, version, colors, fonts, glyphs, and markers.
  • Inventories root and precomposition layers, layer types, image and remote assets, expressions, masks, effects, mattes, and 3D layers.
  • Exports a structured JSON report and labels documented delivery thresholds as heuristics rather than playback guarantees.

How to use Lottie Inspector

Load the Lottie JSON, review the structural details, and use the inspector output to confirm the file matches your implementation or optimization expectations. If the animation behaves unexpectedly in production, compare the inspector results with the working reference file so you can spot structural drift faster.

When this tool is useful

  • Reports source and minified bytes, canvas, duration, frame rate, frames, version, colors, fonts, glyphs, and markers.
  • Inventories root and precomposition layers, layer types, image and remote assets, expressions, masks, effects, mattes, and 3D layers.
  • Exports a structured JSON report and labels documented delivery thresholds as heuristics rather than playback guarantees.

Examples you can test

Load an example, compare the result with the expected output, then replace it with your own input.

Inspect animation metadata

Example input

Lottie JSON with 120 frames at 60 fps

Expected output

Duration, frame rate, dimensions, and layer summary

Metadata helps confirm whether an animation fits the intended UI slot and playback duration.

Review layer complexity

Example input

Lottie file with many shape layers

Expected output

Layer and asset counts for performance review

Complex animations can affect rendering performance, especially on lower-powered devices.

Validation checklist

  • Check dimensions, frame rate, and duration before shipping an animation.
  • Review file size and layer count when performance matters.
  • Preview the animation in the target app or browser context before publishing.

Frequently asked questions

Does this preview the animation?

This tool focuses on inspection and warnings rather than playback controls. Use the Lottie Preview tool when you want interactive playback.

Can it catch heavy Lottie files?

It flags defined review thresholds for JSON bytes, image and embedded assets, duration, frame rate, canvas size, total layers, glyphs, and expressions. These signals do not replace profiling in the target player.

What file types does the Lottie Inspector accept?

The inspector accepts standard UTF-8 Lottie JSON up to 10 MB. DotLottie container files are not unpacked by this workflow.

What kinds of delivery warnings does the inspector flag?

It reports payload thresholds, layer count, raster and remote assets, embedded data, long duration, high frame rate, large canvases, glyph volume, and expressions that may vary across players.

Does the inspector show the animation's actual frame rate and duration?

Yes. The runtime stats panel displays the frame rate (fr), total frames (op minus ip), calculated duration in seconds, and the overall file size so you can assess performance impact.

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