JSON-LD
JSON for Linked Data
JSON-LD is a format for writing structured data as a separate block of code in a web page, apart from the text that shoppers read.
What it means
Structured data has to be written in some format. Google recommends JSON-LD “if your site’s setup allows it”, as “the easiest solution for website owners to implement and maintain at scale”.1
It sits in a block of its own in the page’s code. Google notes that “The markup is not interleaved with the user-visible text”, unlike Microdata and RDFa, which add labels to the page’s own HTML.1
Inside, it is plain text: names and values in quotation marks. The project’s own site calls it “a lightweight Linked Data format” that “is easy for humans to read and write”.2 The names themselves usually come from schema.org.
Think of it like this
It is like a packing list taped to the outside of a box. It describes what is inside, but it is written separately, so you can read it or replace it without unpacking anything.
For example
On a bath’s product page, the JSON-LD block might hold “@type”: “Product”, “name”: “Lowmere single ended bath”, and an offer with “price”: “479.00” and “priceCurrency”: “GBP”. A shopper never sees it; search engines read it.
Why it matters
A theme, plugin or template usually writes the block from your catalogue, and it copies what the catalogue holds without cleaning it. A stock column reading Yes, or a price with a pound sign, goes into every page’s JSON-LD at once.
Not to be confused with
JSON-LD is a format, not a vocabulary. It sets how the data is written; schema.org supplies the words, such as Product, price and availability.
Sources
- Google Search Central. Introduction to structured data markup in Google Search.
- json-ld.org. JSON-LD: JSON for Linked Data.