Pick a type, fill in a short form, and copy clean JSON-LD for your page. Every field is checked as you type against both Google Rich Results and Schema.org (Open Schema), so what you paste is valid before it ships.
Fill in a short form, get clean JSON-LD you can paste into your page <head>. Every field you enter is checked twice as you type: once against Google Rich Results required and recommended properties for the type, and once against Schema.org itself (Open Schema) for valid type and property names and value shapes. You can also paste existing JSON-LD to validate it the same way.
Fill in the form above.
Required properties become errors; recommended properties become warnings. Rules follow Google's structured-data documentation per type.
Checks that the @type is a real Schema.org type, that every property is defined on that type (Schema.org is open, so unknown properties are flagged as warnings, not errors), and that value shapes (URL, date, telephone) are well formed.
Paste a JSON-LD block or a full @graph. It runs through the same two validators without touching the form above.