9 min read read
By Imad Uddin

Convert JSON to CSV in Notepad++: Plugin & Python Methods (2026)

Convert JSON to CSV in Notepad++: Plugin & Python Methods (2026)

You can convert JSON to CSV in Notepad using the JSON Viewer plugin to view the structure, then paste into an online converter for the actual conversion. For developers, a Python script handles it automatically. For non-technical users, an online converter plus Notepad for cleanup is fastest.

Method 1: JSON Viewer Plugin in Notepad

The JSON Viewer plugin helps you view and validate JSON structure, but it doesn't export directly to CSV. Here's what it does:

  1. Open Notepad and go to Plugins > Plugins Admin
  2. Search for "JSON Viewer" and install it
  3. Restart Notepad++
  4. Open your JSON file
  5. Go to Plugins > JSON Viewer > Show JSON Viewer
  6. A tree view panel opens showing your JSON structure

What it can do: View JSON as a collapsible tree, validate syntax, copy individual values.

What it can't do: Export directly to CSV. You'll need to use Method 2 or 3 for the actual conversion.

Method 2: Online Converter + Notepad Cleanup

This is the fastest method for non-developers:

  1. Copy your JSON data
  2. Go to an online JSON to CSV converter (like the JSON to Excel tool which exports CSV)
  3. Paste your JSON and convert
  4. Download the CSV result
  5. Open in Notepad for any cleanup needed

This workflow is fast and requires no coding. For sensitive data, use Method 3 instead.

Method 3: Python Script

For developers or repeated conversions, Python handles this automatically:

import json
import csv

with open('data.json', 'r') as f:
    data = json.load(f)

with open('output.csv', 'w', newline='') as f:
    writer = csv.DictWriter(f, fieldnames=data[0].keys())
    writer.writeheader()
    writer.writerows(data)

Save as convert.py, change data.json to your filename, run python convert.py.

For nested JSON, use pandas:

import pandas as pd

df = pd.json_normalize(pd.read_json('data.json'))
df.to_csv('output.csv', index=False)

Install pandas first: pip install pandas

What to Do When Your JSON Is Nested

Nested JSON can't be directly converted to CSV without flattening first. CSV is a flat table format. Nested objects need to be flattened into columns.

Example nested JSON:

[
  {
    "name": "Alice",
    "address": {
      "city": "New York",
      "zip": "10001"
    }
  }
]

Solution 1: Use the JSON Flattener to flatten your JSON first. It converts address.city to address_city as a single column. Then convert the flattened JSON to CSV.

Solution 2: Use pandas.json_normalize() in Python (shown in Method 3 above). It handles nested structures automatically.

Common Data Issues and How to Fix Them

Real-world JSON files have messy data. Here's how to handle the most common problems you'll hit during conversion.

Missing Keys in Some Objects

Your JSON array has 100 objects, but object 47 is missing the email key. The Python script crashes with a KeyError.

Fix: Change the Python script to handle missing keys:

with open('output.csv', 'w', newline='') as f:
    writer = csv.DictWriter(f, fieldnames=data[0].keys())
    writer.writeheader()
    for item in data:
        writer.writerow({k: item.get(k, '') for k in data[0].keys()})

The .get(k, '') returns an empty string if the key doesn't exist instead of crashing.

Values Containing Commas

Your JSON has "location": "San Francisco, CA". When you convert to CSV, the comma breaks the column structure.

Fix: Python's csv module handles this automatically by wrapping values in quotes. If you're doing manual conversion in Notepad++, wrap any value containing a comma in double quotes:

name,location
Alice,"San Francisco, CA"

Values Containing Quotes

Your JSON has "comment": "She said "hello"". The quotes inside the value break CSV parsing.

Fix: In CSV, escape quotes by doubling them:

name,comment
Alice,"She said ""hello"""

Python's csv module does this automatically. For manual conversion, use find-and-replace to change " to "" inside values.

Large Numbers Treated as Scientific Notation

Your JSON has "id": 1234567890123. Excel opens the CSV and displays it as 1.23E+12.

Fix: This is an Excel problem, not a conversion problem. When opening the CSV in Excel, use Data > From Text/CSV and set the column type to Text instead of General. Or prefix the number with a single quote in the CSV: '1234567890123.

Date Strings Reformatted by Excel

Your JSON has "date": "2026-04-16". Excel opens the CSV and changes it to 4/16/2026 or another format based on your locale.

Fix: Same as above. Use Excel's import wizard and set the column type to Text. Or save the CSV with a .txt extension, which forces Excel to use the import wizard.

Boolean Values

Your JSON has "active": true. CSV doesn't have a boolean type. Should this be true, True, 1, or yes?

Fix: Decide on a convention. Python's csv module writes True and False by default. If you need 1 and 0, convert in the script:

writer.writerow({k: (1 if item.get(k) is True else 0 if item.get(k) is False else item.get(k, '')) for k in headers})

Null Values

Your JSON has "middle_name": null. How should this appear in CSV?

Fix: Python writes None by default. Most tools treat empty cells as null. To write empty strings instead:

writer.writerow({k: (item.get(k) if item.get(k) is not None else '') for k in headers})

Unicode and Special Characters

Your JSON has "name": "José" or emoji. The CSV looks garbled when opened.

Fix: Save the CSV with UTF-8 encoding. In Notepad, go to Encoding > Encode in UTF-8. In Python, specify encoding:

with open('output.csv', 'w', newline='', encoding='utf-8') as f:

If Excel still shows garbled characters, save as UTF-8 with BOM instead. The BOM (Byte Order Mark) tells Excel to use UTF-8 encoding.

Array Values Inside Objects

Your JSON has "tags": ["python", "data", "csv"]. CSV can't represent arrays directly.

Fix: Join array values into a single string with a delimiter:

for item in data:
    for key, value in item.items():
        if isinstance(value, list):
            item[key] = '; '.join(str(v) for v in value)

This converts ["python", "data", "csv"] to python; data; csv in the CSV. Use semicolon instead of comma to avoid breaking CSV structure.

Inconsistent Key Order

Object 1 has keys in order name, age, city. Object 50 has city, name, age. The CSV columns are misaligned.

Fix: Python's csv.DictWriter handles this automatically by using the fieldnames you specify. It writes values in the correct column regardless of key order in the JSON. Always use DictWriter instead of writer for JSON to CSV conversion.

Very Large Files

Your JSON file is 500 MB. Python loads it all into memory and crashes.

Fix: Process the file line by line if it's JSONL format (one JSON object per line):

with open('data.jsonl', 'r') as infile, open('output.csv', 'w', newline='') as outfile:
    first_line = json.loads(infile.readline())
    writer = csv.DictWriter(outfile, fieldnames=first_line.keys())
    writer.writeheader()
    writer.writerow(first_line)
    for line in infile:
        writer.writerow(json.loads(line))

If it's a single large JSON array, you need a streaming JSON parser like ijson. Install with pip install ijson.

Frequently Asked Questions

Can Notepad directly export JSON to CSV?

No. Notepad doesn't have a built-in JSON to CSV export feature. The JSON Viewer plugin lets you view JSON as a tree and copy values, but it doesn't export to CSV format directly. You need to use an online converter, a Python script, or manual conversion with find-and-replace. For quick conversions, paste your JSON into an online tool, then open the result in Notepad for cleanup.

How do I convert nested JSON to CSV?

Nested JSON needs to be flattened first because CSV is a flat table format. Use the JSON Flattener tool at merge-json-files.com to flatten nested objects into single-level keys like address_city and address_zip. Then convert the flattened JSON to CSV. Or use Python with pandas.json_normalize() which handles nested structures automatically. Install pandas with pip install pandas first.

What's the fastest way to convert JSON to CSV without coding?

Use an online JSON to CSV converter. Copy your JSON, paste it into the converter, download the CSV result, then open in Notepad for any cleanup. The JSON to Excel tool at merge-json-files.com exports CSV format and handles most JSON structures. This takes under a minute for typical files. Don't use online converters for sensitive data like API keys or personal information.

Will the column order in the CSV match my JSON key order?

Usually yes, but it depends on the conversion method. Python's csv.DictWriter preserves key order from your JSON. Online converters typically preserve order. Manual conversion in Notepad gives you full control over column order. If order matters for your workflow, verify the first few rows after conversion to confirm columns are where you expect them.

How do I handle JSON arrays when converting to CSV?

If your JSON is an array of objects with consistent keys, it converts directly to CSV where each object becomes a row. If you have arrays inside your objects (nested arrays), you need to flatten them first or handle them separately. Arrays of primitive values (numbers, strings) can be joined into a single CSV cell with a delimiter like semicolon or pipe. Use the JSON Flattener for complex nested arrays.

Related Tools and Guides

  1. JSON to Excel Converter if you need direct Excel output instead of CSV
  2. How to Format JSON in Notepad++ for beautifying and organizing your JSON data
  3. Best JSON Editors for Windows if you want to explore more editor options

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