If you want a free schema markup generator, there are browser tools that build JSON-LD without an install or an account, and they are fine for a one-off block. Our pick is still the seogeoaeo.ai Schema Markup Generator: it is not free, at 3 credits a run, but it previews the block against validator rules and sits next to a checker for the live page, which saves the back-and-forth that free forms leave to you.
Everything below runs in a browser tab. Nothing to download, nothing to configure.
1. seogeoaeo.ai Schema Markup Generator
Pick a type, fill the form, sign in and generate. Sixteen types are on the list, from Article and BlogPosting to Product, Event, Recipe, LocalBusiness and VideoObject, and the tool fetches nothing, so it works on pages that are not live yet.
Why it is first even though it costs credits:
- The output is previewed against validator rules before you paste it anywhere
- The price shows before the run, and a failed run costs nothing
- The Schema Markup Checker on the same site then reads the live page and lists missing properties and missing types
If you want to try the site for free first, its home page gives a free preview of a site's crawl, indexing, on-page and structured data health. That tells you whether you need markup at all before you spend a credit.
2. technicalseo.com Schema Markup Generator
A form-based tool titled Schema Markup Generator (JSON-LD), built by Max Prin. The page shows no sign-up and no pricing, only a tip jar. It is the classic answer to the free search, and for a single, simple block it does the job. Run its output through one of the testers below before it goes live.
3. Google's rich results tester
Not a generator, but the place most people end up. It accepts a URL or a pasted code snippet, and you can edit the snippet and run it again as often as you like. It reads JSON-LD, Microdata and RDFa, and it focuses on the rich result types Google lists, so it tells you about Google features rather than schema.org as a whole.
4. Schema.org's own validator
Schema.org's own checker at validator.schema.org, which took over from Google's old Structured Data Testing Tool. It extracts JSON-LD, RDFa and Microdata, shows the structured data it found and flags syntax mistakes. Use it when your type is not one of Google's rich result features and you still want to know the markup holds up.
5. Writing it yourself
Schema.org documents every type and property, and a JSON-LD block is short enough to write by hand. This is free in money and expensive in attention: nesting an offer, an address or a rating correctly takes a few tries.
Quick comparison
| Option | Builds JSON-LD | Checks it | Cost |
|---|---|---|---|
| seogeoaeo.ai generator | Yes | Validator preview, plus a separate page checker | 3 credits a run |
| technicalseo.com generator | Yes | Pair with a tester | No price shown |
| Rich Results Test | No | Google features | Not a generator |
| Schema Markup Validator | No | Schema.org vocabulary | Not a generator |
| By hand | Yes | No | Your time |
What free does not cover
None of these tools can decide which type your page should use, and none can promise a rich result. Google says valid markup makes a page eligible, not guaranteed. It also asks that every marked-up value appear on the page itself, so copy prices, ratings and dates from what visitors see.
The short answer
For a single block on a hobby site, a free form plus the Rich Results Test is enough. For anything you will maintain, the seogeoaeo.ai generator is worth the 3 credits for the preview and the checker that follows it.