What are you describing?
Paste this into the <head>
What Google makes of each property
Check markup that already exists
Built in this browser — nothing is uploaded and nothing is stored. Valid schema.org is not the same as eligible for a rich result. Schema.org is a vocabulary of some 800 types; Google reads a small part of it, requires particular properties before a page qualifies, and ignores most of the rest. Every property here is marked as required, recommended, or valid-but-ignored — and since Google's requirements are documentation rather than a specification, the table is dated.
The Schema.org Generator needs JavaScript: the form, the markup and the checks are all built in this browser. With JavaScript switched off there is nothing to do the work.