Validates JSON-LD formatting and catches malformed JSON, broken escaping, and parsing failures.
This check parses every `<script type="application/ld+json">` block on your page and validates the JSON syntax. It catches common errors like trailing commas, unescaped special characters, mismatched brackets, and invalid string formatting that would prevent search engines from reading your structured data.
If your JSON-LD has syntax errors, search engines will silently ignore it entirely — your structured data simply won't work. Unlike HTML, JSON is strict about syntax: a single trailing comma or unescaped quote can break the entire block.
Invalid JSON-LD means zero structured data is processed for that block. Any rich results (stars, prices, FAQs, recipes) that depend on it will not appear. This is a silent failure — your pages look normal but lose rich result eligibility.
<!-- INVALID: trailing comma breaks parsing -->
<script type="application/ld+json">
{
"@type": "Article",
"headline": "My Post", <!-- trailing comma! -->
}
</script>
<!-- VALID: no trailing comma -->
<script type="application/ld+json">
{
"@type": "Article",
"headline": "My Post"
}
</script>Run a free audit to see how your site performs on JSON-LD Syntax Validation and 159 other checks.
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