1️⃣ Why Use JavaScript for Structured Data? #
- Dynamic websites (React, Vue, Angular, etc.) or sites that load product/event data on the fly.
- Useful for fast-changing content (e.g., price, availability, event timings).
- Ideal if you want to avoid hardcoding schema in HTML.
⚠ Caution for eCommerce: For products, frequent price/availability changes via JS may cause delays in Shopping crawls — keep server capacity ready.
2️⃣ Options to Generate Structured Data #
A. Google Tag Manager (No Code Changes Needed) #
- Add Custom HTML Tag with JSON-LD.
- Use variables to dynamically pull page info.
Example:
<script type=”application/ld+json”>
{
“@context”: “https://schema.org/”,
“@type”: “Event”,
“name”: “{{event_name}}”,
“startDate”: “{{event_start}}”,
“endDate”: “{{event_end}}”,
“location”: {
“@type”: “VirtualLocation”,
“url”: “{{event_url}}”
},
“organizer”: {
“@type”: “Organization”,
“name”: “FSIDM”,
“url”: “https://fsidm.in”
}
}
</script>
➡ Best for: Marketing teams (no dev needed).
B. Custom JavaScript (Directly in Site Code) #
Fetch or build JSON-LD dynamically and inject into <head>:
fetch(‘https://api.example.com/events/101’)
.then(response => response.json())
.then(data => {
const script = document.createElement(‘script’);
script.type = ‘application/ld+json’;
script.textContent = JSON.stringify(data);
document.head.appendChild(script);
});
➡ Best for: Dev teams or SPA frameworks.
C. Server-Side Rendering (SSR) #
Generate JSON-LD during page rendering (fastest & most crawlable):
<script type=”application/ld+json”>
{
“@context”: “https://schema.org/”,
“@type”: “Course”,
“name”: “FSIDM Digital Marketing Course”,
“description”: “Hands-on training in SEO, Paid Ads, and AI Tools.”,
“provider”: {
“@type”: “Organization”,
“name”: “FSIDM”,
“url”: “https://fsidm.in”
}
}
</script>
➡ Best for: SEO-focused websites where Google indexing speed matters.
3️⃣ Testing Your Implementation #
- Use Rich Results Test → https://search.google.com/test/rich-results
- Always Test URL (not just code) for JS implementations.
- Check Search Console > Enhancements for errors/warnings.