Structured Data

Product Schema for Industrial Specifications

Use the Product type and, for every characteristic your catalogue has that the schema.org vocabulary does not name directly, describe it with additionalProperty and PropertyValue. That pair is exactly what schema.org documents for a property without its own name in the vocabulary, and it is the way to turn a specification table — voltage, flow rate, pressure rating, tolerance — into something a crawler or a language model can read as structured data instead of guessing from a PDF table. Google adds that structured product data can make the listing richer in Search, in Google Images and in Google Lens, which is a reason to do this beyond any effect on ranking.

Diagnose the Product Pages Back to Industrial Knowledge Architecture

What schema.org Documents

Product

The base type for any item offered for sale, according to schema.org

additionalProperty

Property that holds a PropertyValue for a characteristic without a dedicated name, per schema.org

Richer listing

Google says product data can appear richer in Search, Images and Lens

Listing types Google distinguishes: product snippets and merchant listings

01The Direct Answer

How do I use product schema for technical specifications?

Direct Answer

Wrap the item in Product and put every named attribute — name, description, image, brand — in the properties schema.org already defines. Whatever is left over goes into a list of additionalProperty entries, each one a PropertyValue with a name and a value.

An industrial datasheet rarely fits the handful of properties a consumer product uses. A pump has flow rate, head, inlet diameter, material, IP rating. None of those has a dedicated schema.org property with that exact meaning, and PropertyValue exists precisely for that gap: a name field and a value field, repeated once per specification, inside the additionalProperty array of the Product.

02Product and PropertyValue

The two types that carry a specification table

According to schema.org, the Product type carries the properties every buyer expects — name, image, brand, description, offers — and additionalProperty is the documented escape hatch for a characteristic without its own property in the vocabulary. Each additionalProperty entry is a PropertyValue, which pairs a human-readable name with a value and, when there is one, a unit of measurement.

Named property

name, description, image, brand, sku, offers

Use these directly on the Product node. They already have a defined meaning that Google and other consumers of the vocabulary understand without ambiguity.

Technical specification

additionalProperty → PropertyValue

Voltage, flow rate, pressure rating, tolerance, material, certification code. Each becomes one PropertyValue object, and the list can be as long as the datasheet requires.

03What Google Does With It

Snippet or merchant listing, and a richer result

Google's documentation for product structured data draws a line between two outcomes. A page without a direct purchase flow can earn a product snippet — price, availability, review information shown alongside the regular result. A page where the visitor can buy directly is treated as a merchant listing, with its own eligibility rules. Most industrial catalogue pages, where the outcome is a quote request rather than a checkout, fall into the first category.

According to Google, with product structured data in place the information can appear richer in Search, in Google Images and in Google Lens. None of this is a promise of a higher position — it is a description of how the same information can be displayed once a machine can parse it instead of extracting it from a table image or an inconsistent PDF layout. See why a PDF catalogue is hard for AI to read.

04Building the Schema

From the spec table to the additionalProperty array

Four Steps

1. List every row

Take the specification table as it exists today — the same one engineering already approved — and turn every row into a name/value pair.

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2. Separate named from technical

Name, description, image and brand go into the properties Product already has. Everything else becomes a PropertyValue.

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3. Add the unit where it exists

A number without a unit is ambiguous to a machine. Flow rate in m³/h is not the same claim as flow rate in L/min, and PropertyValue has a field for that.

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4. Publish it with the page, in HTML

The schema describes what is on the page. It does not replace a readable HTML table — it sits beside one.

A table that already reads well to a person and to a machine, before any schema is added, is the subject of the page on a specification table readable by AI.

05The Most Common Mistake

Schema without a matching sentence on the page

For Roberto Wydra, founder of RudekWydra, the recurring mistake in industrial catalogues is not the absence of schema markup — it is schema built to describe specifications that the visible page never states in readable text. "A markup that repeats a number the page itself does not say, in a sentence a person can read, is decoration. The structured data has to describe what is already there, not compensate for what is missing", he says. This is a thesis about method, not a measured outcome, and it is also why this hub keeps insisting on a readable data-first approach before adding any markup: organize the data before the media.

Schema describes what is on the page. It does not invent it.

Product schema is one layer of a larger structuring effort. It complements, and does not replace, general-purpose structured data for AI search — the structured data for generative search page — and FAQ markup for the questions buyers actually ask, covered in the industrial FAQ schema page.

06FAQ

FAQ

How do I use product schema for technical specifications? +

Wrap the item in the Product type from schema.org and put every characteristic without its own dedicated property into an additionalProperty list, one PropertyValue per specification. Named attributes like name, description, image and brand use the properties Product already defines.

What is PropertyValue for? +

According to schema.org, PropertyValue pairs a name with a value, and optionally a unit, for a characteristic that has no dedicated property in the vocabulary. It is the mechanism additionalProperty uses to carry a specification table inside a Product node.

Does product schema improve my Google ranking? +

Google states that structured product data can make the information appear richer in Search, in Google Images and in Google Lens. That is a description of display, not a documented ranking effect, and this page does not claim one.

What is the difference between a product snippet and a merchant listing? +

According to Google, a product snippet applies to a page without a direct purchase flow, while a merchant listing applies to a page where the visitor can buy directly, with its own eligibility rules. An industrial catalogue page that ends in a quote request, not a checkout, typically fits the first category.

Can I put a specification without a numeric unit inside PropertyValue? +

Yes. PropertyValue accepts a text value, such as a material or a certification code, and a numeric value with a unit, such as a flow rate or a voltage. The rule is that whatever a person reads on the page should be the same thing the schema states, in the same terms.

Does product schema replace FAQ schema or general structured data for AI search? +

No. Product schema describes an item and its specifications. FAQ schema describes the questions a buyer asks about it, and general structured data for generative search covers the page as a whole. They are complementary layers, not substitutes for one another.

Should I add schema before or after fixing the visible specification table? +

After. Schema markup that repeats a specification the visible page never states in readable text describes nothing real. Fix the table a person reads first, then mirror it in additionalProperty.

Does this apply to a page with dozens of product variants? +

Yes, and it matters more there. schema.org supports a ProductGroup for a family of variants sharing most properties, with additionalProperty used for what differs between them. The larger the specification table, the more a machine benefits from having it structured instead of embedded in a PDF.

See whether your product pages are readable to a machine

The diagnosis checks whether the specification table, the schema and the page text say the same thing, before proposing any change.

Diagnose My AccountDiagnosis first, schema afterwards