📊 Vega-Lite Spec Validator

Validate Vega-Lite JSON structure locally with schema-path diagnostics.

Runs locally in your browser. Uses the disclosed Vega-Lite v5 structural preflight contract, capped at 250,000 bytes, with no chart rendering.

Vega-Lite JSON

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": {
    "values": [
      {
        "category": "A",
        "value": 4
      },
      {
        "category": "B",
        "value": 7
      }
    ]
  },
  "mark": "bar",
  "encoding": {
    "x": {
      "field": "category",
      "type": "nominal"
    },
    "y": {
      "field": "value",
      "type": "quantitative"
    }
  }
}

Validation report

Runs in your browser

Runs locally in your browser with no chart rendering or server upload.

Include current input in shared/debug payload

What this tool does

Parses Vega-Lite JSON and checks a dependency-free structural subset with actionable JSON-path diagnostics.

Why it is useful

It catches malformed JSON, missing marks, invalid encoding channels and types, and unsafe input size before a spec reaches a renderer.

Pinned validation contract

Vega-Lite v5 structural preflight. This is a bounded structural validator, not the complete upstream JSON schema and not a chart renderer.

Privacy note

Runs locally in your browser. Specs and reports are never uploaded.

Important limitation

A passing report means the disclosed structural checks passed; validate renderer-specific behavior against your pinned Vega-Lite runtime.

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