Convert Nested JSON to Flat CSV

Flatten complex, deeply nested JSON objects into clean CSV rows — automatically handled.

By 📅 Updated ⏱ 4 min read
Key Takeaways (TL;DR)

Nested JSON objects are flattened to CSV using dot notation (e.g., user.address.city becomes a column header). Arrays become comma-separated cell values. No depth limit — works with any JSON structure.

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The Nested JSON Problem

Real-world JSON from APIs is rarely flat. You get nested objects like {"user": {"address": {"city": "Seattle"}}}. Spreadsheets need flat rows and columns. Our tool automatically flattens nested structures using dot notation.

How Flattening Works

Nested keys are joined with dots: user.address.city becomes a CSV column header. Arrays are converted to comma-separated strings within cells. This preserves all data while making it spreadsheet-compatible.

Example: API Response to CSV

A typical REST API response with nested user profiles, addresses, and order histories converts to a flat CSV where each column represents a specific data point. No data is lost in the process.

Frequently Asked Questions

How deep can nesting go?

There's no depth limit. Objects nested 10+ levels deep will all be flattened correctly.

What happens to arrays inside objects?

Array elements are joined with commas within a single cell. For example, ["tag1","tag2"] becomes "tag1,tag2" in the CSV.

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