JavaScript Object Notation (JSON) is everywhere — APIs, config files, logs, databases, message queues, and more. Its simplicity makes it powerful, but poorly formatted JSON can cause bugs, broken APIs, unreadable logs, and developer frustration.

This guide covers the best JSON formatting practices every developer should follow, along with examples and tools that make your workflow easier.

Why JSON Formatting Matters

Well-formatted JSON: • Enhances readability • Reduces parsing errors • Improves collaboration across teams • Helps debug APIs and microservices • Ensures consistency in large applications • Makes automated tools work properly

When JSON is clean and predictable, everything becomes easier — from API integration to debugging production issues.

  1. Always Use a JSON Validator or Formatter

Before sending JSON in an API request, storing it in config files, or committing it to Git, validate and format it properly.

Example of badly formatted JSON:

{"name":"John","age":25,"skills":["js","react","node"]}

A properly formatted version:

{ "name": "John", "age": 25, "skills": ["js", "react", "node"] }

👉 Use our free JSON Viewer & Formatter: https://utilityflux.pages.dev/tools/productivity/json-viewer

  1. Use 2 Spaces for Indentation

The widely accepted standard: • 2 spaces for indentation • No tabs, no 4-space indent unless project requires it

Why? • Works consistently across editors • Smaller file sizes • Clean & readable

Example:

{ "user": { "id": 101, "active": true } }

  1. Keys Should Always Be Strings

Correct:

{ "status": "success" }

Incorrect:

{ status: "success" }

Although some JavaScript objects allow unquoted keys, JSON never does.

  1. Avoid Trailing Commas

❌ Invalid JSON:

{ "name": "Alice", "age": 30, }

Trailing commas break parsers and APIs.

Always end lists cleanly:

✔ Correct:

{ "name": "Alice", "age": 30 }

  1. Use Consistent Naming Conventions

Choose one convention and stick to it across all JSON structures.

Common styles: • camelCase → recommended for JavaScript • snake_case → good for Python ecosystems • kebab-case → rarely used in JSON keys

✔ Good:

{ "userName": "vijaySaw" }

❌ Bad:

{ "user_Name": "vijaySaw" }

  1. Keep JSON Lean — Avoid Unnecessary Nesting

Deeply nested structures become difficult to maintain.

❌ Too deep:

{ "a": { "b": { "c": { "d": "value" } } } }

✔ Cleaner:

{ "level": "value" }

  1. Use Arrays When Representing Lists

Don’t create item1, item2, etc.

❌ Bad design:

{ "item1": "pen", "item2": "book", "item3": "notebook" }

✔ Correct:

{ "items": ["pen", "book", "notebook"] }

  1. Encode Special Characters Properly

When dealing with URLs, HTML, or multi-language text, escape the characters:

Example:

{ "url": "https://example.com?q=hello%20world" }

Use these tools if needed: • URL Encoder / Decoder: https://utilityflux.pages.dev/tools/productivity/converters/url

  1. Keep Large JSON Files Structured and Modular

When JSON becomes too large: • Break it into smaller sections • Use references or IDs • Keep reusable configs separate

Example of splitting config files:

config/ ├─ database.json ├─ cache.json └─ api.json

  1. Document Your JSON Structure

Especially for APIs, document: • Required fields • Optional fields • Accepted values • Example responses

Example:

{ "id": 101, "status": "active", "roles": ["admin", "editor"] }

Common JSON Mistakes to Avoid

❌ Missing commas ❌ Unquoted keys ❌ Duplicate keys ❌ Incorrect data types ❌ Trailing commas ❌ Mixing tabs and spaces

Useful Tools for JSON Work

Here are free tools that make JSON easier to work with: • JSON Viewer / Formatter https://utilityflux.pages.dev/tools/productivity/json-viewer • XML ↔ JSON Converter https://utilityflux.pages.dev/tools/productivity/converters/xml-json • YAML ↔ JSON Converter https://utilityflux.pages.dev/tools/productivity/converters/yaml-json • CSV ↔ JSON Converter https://utilityflux.pages.dev/tools/productivity/converters/csv-json

These tools help ensure your data is always clean and usable.

Conclusion

JSON is simple — but good JSON takes discipline.

By following these best practices: • Your APIs will be easier to integrate • Your configuration files become clean and readable • Your debugging becomes faster • Your team will thank you

Use proper formatting, consistent structure, and validation tools to keep your JSON clean and reliable.

Related Tools • 👉 JSON Viewer — https://utilityflux.pages.dev/tools/productivity/json-viewer • 👉 XML ↔ JSON Converter — https://utilityflux.pages.dev/tools/productivity/converters/xml-json • 👉 YAML ↔ JSON Converter — https://utilityflux.pages.dev/tools/productivity/converters/yaml-json • 👉 CSV ↔ JSON Converter — https://utilityflux.pages.dev/tools/productivity/converters/csv-json