Convert Nested JSON to CSV

Conversion Rules That Work

• Flatten nested keys using dot-path columns (example: user.profile.age).
• Decide array strategy: explode rows vs joined cell values.
• Normalize missing keys as blank/null for consistent headers.

Example

// Input JSON
{
  "user": { "id": 7, "name": "Ava" },
  "tags": ["admin", "editor"]
}

// CSV headers
user.id,user.name,tags

Workflow

1. Validate and format input first.
2. Run JSON to CSV.
3. Round-trip check with CSV to JSON for data loss detection.
4. Use JSON Diff between source and rehydrated output.

Common Pitfalls

• Arrays of objects that should become multiple rows but are collapsed into a cell.
• Nested keys that disappear because headers are inferred from the first row only.
• Inconsistent types between rows (string vs number).

FAQ

Should I flatten all nested objects?

Flatten only the parts required by downstream tools. Deep flattening can make CSV hard to work with.

How do I preserve arrays?

Either explode arrays into multiple rows or join with a delimiter; pick one and stay consistent.