isSemantic.net
isSemantic.net is a free web tool for working with structured data.
What isSemantic.net is
isSemantic.net is a free web tool for working with structured data. It validates JSON-LD, RDFa and Microdata against Schema.org, Google Search, Facebook Open Graph, Twitter Cards, Facebook App Links and HTML outline semantics. Markup that uses vocabularies beyond Schema.org is set apart in an “Other vocabulary markup” section rather than validated. Its generator creates or edits markup using examples from Google Search, Schema.org, Open Graph and Twitter Cards; users can also import a snippet or add Schema.org properties. Google and Schema.org output is JSON-LD, while Open Graph and Twitter Cards output is RDFa. For RDF, the visualizer provides a graph, a triples table and a hierarchical view. It accepts formats including JSON-LD, Microdata, N-Quads, N-Triples, N3, RDFa, RDF/XML, TriG and Turtle, plus provisionally supported RDF-star formats. The converter accepts a URL or code snippet, detects input formats and converts between RDF serializations. The service is limited to private, non-commercial use. Its terms say it does not store or redistribute accessed public structured data, while the site uses cookies and stores IP addresses for core features and legal claims.
Good
- Free web tool.
- Validates JSON-LD, RDFa and Microdata.
- Visualizes RDF in three views.
- Converts among RDF serialization formats.
Watch out
- Terms restrict use to private, non-commercial purposes.
- Non-Schema.org vocabularies are not validated.
- Correct validation does not guarantee search-result display.
- Cookies and IP-address storage are disclosed.
Who it suits
It suits people who need browser-based tools to validate or transform structured data for private, non-commercial work. Its visualizer and generator may also help users who need to inspect RDF or prepare markup from examples.
Verdict
isSemantic.net brings validation, generation, visualization and conversion together in a free web tool. Check its vocabulary limitation and private-use terms before relying on it for a project.
The facts
Each one read from isSemantic.net's own pages, with the date it was checked.
What it does
- Data handling
- The terms say the service accesses third-party websites only to analyze publicly available structured data and does not store or redistribute that accessed data.checked 4 Oct 2026
- Generated formats
- The generator outputs JSON-LD for Google and Schema.org markup and RDFa for Open Graph and Twitter Cards.checked 8 Oct 2026
- Generator
- The generator creates and edits markup from Google Search, Schema.org, Open Graph and Twitter Cards examples, and supports custom Schema.org snippets.checked 8 Oct 2026
- Generator formats
- Generated Google and Schema.org markup is provided as JSON-LD, while Open Graph and Twitter Cards markup is provided as RDFa.checked 4 Oct 2026
- Privacy and cookies
- The site says it uses cookies and similar technologies, offers consent controls, and says IP addresses are needed for main features and stored for legal claims.checked 8 Oct 2026
- Purpose
- isSemantic.net validates, visualizes, generates and converts structured data on websites.checked 8 Oct 2026
- RDF conversion
- The converter can take data from a web address or pasted markup and can auto-detect the input format.checked 8 Oct 2026
- RDF converter
- The converter accepts a web address or code snippet, can auto-detect input format and converts between RDF serialization formats including RDF-star formats.checked 4 Oct 2026
- RDF formats
- The visualizer supports formats including JSON-LD, Microdata, N-Quads, N-Triples, N3, RDFa, RDF/XML, TriG and Turtle.checked 8 Oct 2026
- RDF-star support
- RDF-star conversion and validation are supported, but the site describes this support as provisional because RDF-star is an unofficial draft.checked 8 Oct 2026
- RDF visualization
- The visualizer displays RDF triples as a graph and lists their relations in a table, in the browser without software installation.checked 8 Oct 2026
- RDF visualizer
- The visualizer displays RDF data as a graph and also lists triples in a table and hierarchical view.checked 4 Oct 2026
- Result disclaimer
- The validator says it does not guarantee that correctly marked-up data will appear in search results.checked 8 Oct 2026
- Service limitation
- The site does not guarantee that correctly validated structured data will appear in search results.checked 4 Oct 2026
- Support
- The maker provides a Contact us link and says users with queries about the terms can contact them, but the opened pages do not state a support response commitment.checked 4 Oct 2026
- Usage terms
- The terms restrict use to private, non-commercial purposes and say access may be suspended, restricted or terminated at any time without notice.checked 4 Oct 2026
- Use restriction
- The terms state that use is for private, non-commercial purposes and that accessed third-party structured data is not stored or redistributed.checked 8 Oct 2026
- Validation formats
- The validator accepts JSON-LD, RDFa and Microdata.checked 8 Oct 2026
- Validation limitation
- Markup using vocabularies beyond Schema.org is shown in an Other vocabulary markup section and is not validated by the tool.checked 8 Oct 2026
- Validator
- The validator checks Schema.org, Google Search, Facebook Open Graph, Twitter Cards, Facebook App Links and HTML heading semantics.checked 8 Oct 2026
- Validator limitation
- Markup using vocabularies other than Schema.org is shown in an “Other vocabulary markup” section rather than validated.checked 4 Oct 2026
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