Semantic Versioning Validator - Online Check Semver Syntax
Validate and compare semantic version strings. Check if a version satisfies a range (e.g., ^1.2.3). Visual breakdown of major.minor.patch. Local only.
UD5 Toolkit
Validate & debug your structured data markup instantly — 100% client-side, no data sent anywhere.
Validation results will appear here
Paste your JSON-LD and click Validate
<script type="application/ld+json"> tags. Unlike Microdata or RDFa, JSON-LD doesn't require modifying your HTML elements — you simply place it in the page head or body. It helps search engines understand your content better, enabling rich results like product carousels, review stars, FAQ accordions, and knowledge graph panels, which can significantly improve click-through rates."https://schema.org"; Trailing commas after the last property in an object or array (not valid in JSON); Unquoted property names — all keys must be double-quoted; Using single quotes instead of double quotes for strings; Missing @type — while technically optional, omitting @type often prevents rich result eligibility; Incorrect nesting — e.g., putting an address string where an address object with @type is expected; Comment syntax — JSON doesn't support // or /* */ comments. Always validate before publishing.@context property defines the vocabulary used in your structured data. For SEO purposes, you should almost always use "https://schema.org" (or the older "http://schema.org"). This tells search engines that your property names follow Schema.org definitions. You can also use an array of contexts if you're mixing multiple vocabularies, or an inline object to define custom terms. However, for Google rich results, stick with the standard Schema.org context. Without a valid @context, your JSON-LD is just plain JSON — not linked data.<script type="application/ld+json"> blocks on a single page. Each block should contain a complete, self-contained JSON-LD object. Alternatively, you can use a JSON array with the @graph keyword to combine multiple entities in one script block. Both approaches are valid and supported by Google. Common examples include having separate blocks for BreadcrumbList, Product, Organization, and Article on the same page — each describing different aspects of your content.itemscope, itemprop, itemtype) directly on existing elements, which can clutter your markup. RDFa is similar to Microdata but uses different attributes (vocab, typeof, property). Google recommends JSON-LD for most use cases because it's cleaner, less error-prone, and easier to manage with modern JavaScript frameworks and tag managers.Validate and compare semantic version strings. Check if a version satisfies a range (e.g., ^1.2.3). Visual breakdown of major.minor.patch. Local only.
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