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Schema Validation

Sitebulb audits structured data from two perspectives which take the form of Schema Validation and Google Features Validation. This page focuses on Schema validation, but you can find out more about Google Features validation in our guide to Google Features validation.

What is Schema Validation?

When doing an audit with structured data functionality enabled, Sitebulb looks for structured data on each page, and when found, carries out a series of checks to validate the code against the Schema.org vocabulary specification and guidelines.

It’s worth pointing out that the Schema.org data model is designed to be flexible and used in whatever way the publisher sees fit. However, to help users communicate structured data in a form most likely to be machine readable, Sitebulb’s validation is based on conformance to the Schema.org documentation. In other words, there are no strict rules that structured data must conform to, but if you want to help others interpret your structured data, then ensuring it validates against the guidelines is important.

What are Schema Validation Errors?

Schema validation errors are the messages that Sitebulb returns when it finds structured data which does not comply with the Schema.org vocabulary specification and guidelines. Within the tool these errors will give brief details of the issue along with links to relevant resources. This document provides additional information and resources for each error type, including where possible:

  • What Schema the validation error relates to.
  • What the issue is / why the error is triggered.
  • Advice on how to resolve the issue.
  • Supporting links to relevant Schema.org documentation.

Types of Schema Validation Error

Below is a list of all of the Schema validation error types which can be triggered when carrying out a structured data audit using the Sitebulb tool, along with supporting documentation where appropriate.

JSON script broken

This error indicates an issue with the JSON syntax which needs to be fixed.

In some cases this type of error may mean that Sitebulb is unable to fully parse the JSON and structured data within it.

Missing schema type

Schema is made up of a set of ‘types’ contained within the Schema.org vocabulary. Every structured data entity must have a defined ‘type’.

This error indicates that no Schema type has been set for this entity.

Not a recognised schema type

Schema is made up of a set of ‘types’ contained within the Schema.org vocabulary. Every structured data entity must have a defined ‘type’.

This error indicates that the ‘type’ defined is not recognised as an existing Schema type.

This is usually the result of a typo or incorrect input. Check that your field matches the Schema naming of the type exactly.

There may however be instances where the type is intended as an extension of the core Schema.org vocabulary.

Not a recognised schema property

Each structured data entity is made up of a number of properties.

This error indicates that the property in your structured data entity is not recognised as a Schema.org property.

This is usually the result of a typo or incorrect input. Check that your property name exactly matches the Schema.org naming of the property.

To see the properties available for your entity, look up your entity schema type on Schema.org.

Not a valid property for this type

For each Schema type, there is a list of allowed properties which can be used.

This error indicates that although the property is recognised by Schema.org, it does not belong to this entity’s class or type.

To see the properties which are valid for your entity, look up the schema type on Schema.org.

Empty property value

Every entity property must contain a value.

For example, if an entity contained the property ‘name’, then the property value would in turn be the actual name (e.g. “Fred”).

This error indicates that the property is empty and contains no data/value.

Not a valid property data type

For each Schema property there is an ‘expected type’ for what it should contain. This expected type can either be a data type, or property type to be nested. Many properties have multiple expected types which can be used.

This error indicates that the data type currently set is not a valid data type for this property.

Invalid property value data type

This error indicates that the value currently within this property does not match the expected type for that property.

For each Schema property there is an ‘expected type’ for what it should contain. This expected type can either be a data type or a nested property type. Many properties have multiple expected types which can be used.

For example: within a Person type entity, the expected type for familyName is ‘text’, whereas the expected type for birthDate is ‘date’.

Incorrect schema enumeration value

For some Schema properties, there are a predefined set of values or ‘enumerations’ which should be used.

For example, when using the itemCondition property, one of the following enumeration values should be used: DamagedCondition, NewCondition, RefurbishedCondition, or UsedCondition.

This error indicates the current property value does not match any of the pre-defined enumerations for that property type.

The enumeration values which can be used for a given property type can usually be found under the ‘Enumeration Members’ heading at the bottom of Schema.org pages for the corresponding property type.

Property has been superseded

As the Schema.org vocabulary develops, some properties get replaced. Or in other words they’re superseded by other properties.

This error indicates that the property used has been superseded by another, and should therefore be replaced.

Details will be given in the Sitebulb tool for which property it has been superseded by along with a link to the corresponding Schema.org webpage.

Invalid boolean format

A Boolean is a Schema data type.

This error indicates that the current Boolean value is invalid.
The value of a Boolean should always be ‘True’ or ‘False’.

Variations in format or spelling may cause issues.

Invalid DateTime format

DateTime is a Schema data type.

This error indicates that the current DateTime value does not match the format specified by Schema.org.

The date and time must use ISO 8601 standard format:
[-]CCYY-MM-DDThh:mm:ss[Z|(+|-)hh:mm]

See the Schema.org DateTime data type documentation for the format specification.

Invalid Float format

Float is a Schema data type which consists of a floating number.

This error indicates that the current Float value does not match the format specified by Schema.org.

See the Schema.org Float data type documentation for the format specification.

Invalid Number format

Number is a Schema data type.

This error indicates that the current Number value does not match the format specified by Schema.org.

See the Schema.org Number data type documentation for the format specification.

Invalid Integer format

Integer is a Schema data type.

This error indicates that the current Integer value does not match the format specified by Schema.org.

See the Schema.org Integer data type documentation for the format specification.

Invalid Quantity format

Quantity is a Schema property type.

This error indicates that the current Quantity value does not match the format specified by Schema.org.

See the Schema.org Quantity property type documentation for the format specification.

Invalid Mass format

Mass is a Schema property type.

This error indicates that the current Mass value does not match the format specified by Schema.org.

See the Schema.org Mass property type documentation for the format specification.

Invalid Energy format

Energy is a Schema property type.

This error indicates that the current Energy value does not match the format specified by Schema.org.

See the Schema.org Energy property type documentation for the format specification.

Invalid Distance format

Distance is a Schema property type.

This error indicates that the current Distance value does not match the format specified by Schema.org.

See the Schema.org Distance property type documentation for the format specification.

Invalid ISO-8601 Duration format

Duration is a Schema property type which uses the ISO-8601 format.

This error indicates that the current Duration value does not match the format specified by Schema.org.

See the Wikipedia ISO-8601 standards page for the duration format specification required.

Invalid URL format

URL is a Schema data type.

This error indicates that the current URL value does not match the format specified by Schema.org.

See the Schema.org URL data type documentation for the format specification.

Schema type uses incorrect case

Schema types are case sensitive and therefore must always follow the formatting specified by Schema.org

This error indicates that incorrect case formatting has been used for this schema type.

To check for the correct case formatting, find the schema type on Schema.org.

Schema property uses incorrect case

Schema properties are case sensitive and therefore must always follow the formatting specified by Schema.org

This error indicates that incorrect case formatting has been used for this schema property.

To check for the correct case formatting, find the schema type on Schema.org and look up the property within the Schema type documentation.