💼 Pro version available
Adds support for custom CSV delimiters and extended options.
👉 https://minitoollab.gumroad.com/l/json2csvpro?_gl=11cio27s_gaMTE2NzE5NTc0MS4xNzY1ODMzOTgy_ga_6LJN6D94N6*czE3NjYxNzMyNTgkbzQkZzAkdDE3NjYxNzMyNTgkajYwJGwwJGgw

json2csv

A predictable CLI to flatten JSON into CSV. Built for API responses, logs, and anything else that refuses to behave.

Why this exists

If you’ve ever:

• Exported JSON from an API and needed it in Excel
• Shared data with someone who does not speak JSON
• Debugged deeply nested payloads
• Used a random online JSON-to-CSV site you didn’t trust

This tool is for you.

json2csv turns messy, nested JSON into a clean, scriptable CSV you can use anywhere.

Install

npm

npm install -g json2csv

Note: If you publish under a different npm package name (recommended for uniqueness), update the install command accordingly.

Usage

From a file:

json2csv input.json > output.csv

From stdin:

cat input.json | json2csv > output.csv

From an API:

curl -s https://api.example.com/data | json2csv > data.csv

Flattening rules

• Nested objects become dot-notation columns
  user.profile.name

• Arrays of primitives are joined with |
tags → "a|b|c"

• Arrays of objects become indexed columns
  items[0].id, items[1].id

• Empty or missing values are preserved as empty cells

• Column order is stable and alphabetical

Example

Input

{
  "id": 1,
  "user": { "profile": { "name": "Tim" } },
  "tags": ["x", "y"],
  "items": [
    { "sku": "A1", "qty": 2 },
    { "sku": "B2", "qty": 1 }
  ]
}

Output

id,items[0].qty,items[0].sku,items[1].qty,items[1].sku,tags,user.profile.name
1,2,A1,1,B2,x|y,Tim

Design goals

• Predictable output
• Safe for scripts and CI
• No config files
• No external services
• No telemetry

License

MIT