Question 1

How do you convert JSON to CSV?

Accepted Answer

To convert JSON to CSV, extract the keys from JSON objects to create CSV headers, then map each object's values to a corresponding row. For a JSON array like [{"name":"Alice","age":30}], the output is a CSV with 'name,age' as the header row and 'Alice,30' as the data row. Our tool handles this automatically, including nested object flattening.

Question 2

Can nested JSON be converted to flat CSV?

Accepted Answer

Yes, nested JSON can be flattened into CSV format. Nested properties are typically represented using dot notation in column headers. For example, {"user":{"name":"Alice","address":{"city":"NYC"}}} becomes columns 'user.name' and 'user.address.city'. Arrays within objects can be joined as comma-separated values or split into multiple columns.

Question 3

How are JSON arrays handled in CSV conversion?

Accepted Answer

When a JSON property contains an array, there are several approaches: the array can be serialized as a JSON string in a single CSV cell, joined with a delimiter (like semicolons), or expanded into multiple numbered columns (e.g., 'tags.0', 'tags.1'). The best approach depends on how the CSV will be used downstream.

Question 4

What happens to null values in JSON to CSV?

Accepted Answer

Null values in JSON are typically converted to empty cells in CSV output. The string 'null' is not inserted because it could be confused with actual text data. Similarly, undefined properties in some JSON objects (when objects have different shapes) result in empty cells for those columns. Boolean values are converted to their string representations 'true' and 'false'.

Question 5

How do you export JSON to Excel?

Accepted Answer

To get JSON data into Excel, first convert it to CSV format using a JSON to CSV converter. Then open the CSV file in Excel, which will automatically parse the comma-separated data into columns. Alternatively, Excel can directly import JSON via Power Query (Get Data > From JSON), which handles nested structures and data type detection automatically.

Question 6

What is JSON flattening?

Accepted Answer

JSON flattening is the process of converting a nested, hierarchical JSON structure into a flat, single-level object. Each nested path becomes a dot-separated key. For example, {"a":{"b":{"c":1}}} flattens to {"a.b.c":1}. This is essential for CSV conversion because CSV is inherently a flat, tabular format that cannot represent hierarchy directly.

Question 7

Which is more efficient, JSON or CSV?

Accepted Answer

CSV is more space-efficient for flat, tabular data because it has minimal overhead (just commas and newlines). JSON repeats key names for every object, adding significant overhead. However, JSON is more efficient for sparse data (where many fields are empty) and complex nested structures. For a dataset with 10 columns and 1000 rows, CSV can be 30-50% smaller than the equivalent JSON.

JSON to CSV Converter