Determining JSON types in BigQuery

UpdatedMarch 2, 2026

•1 min read

Constantin Lungu

Senior Data Engineer • Contractor / Freelancer • GCP & AWS Certified

Part of seriesBigQuery JSON

Here's a mildly interesting function if you're working with JSON in BigQuery.

JSON_TYPE takes in a JSON value and returns the name of the respective JSON type (object, array, string, number, boolean, null) as a STRING.

See below an illustration of it in action.

Also, given we use the native JSON datatype, notice how we can just access the first ([0]) element in an ARRAY or a field directly by dot notation.
This you cannot do with a JSON-like STRING (not without parsing). Check out my previous post about JSON vs JSON-like string.

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BigQuery JSON

Part 4 of 6

Working with JSON in BigQuery — the native JSON datatype, extracting and transforming JSON data, LAX conversion functions, and handling semi-structured payloads.

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BigQuery JSON

JSON datatype vs JSON-like STRING in BigQuery

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