Common JSON Mistakes Beginners Make

JSON (JavaScript Object Notation) is simple, but many beginners still make small mistakes that cause huge problems. Understanding these common errors can save you hours of debugging. Let's dive into them!

1. Forgetting Double Quotes

In JSON, both keys and string values must always be enclosed in double quotes " ". Beginners often use single quotes or forget the quotes entirely.

Wrong:
{name: 'John'}

Correct:
{ "name": "John" }
  

2. Trailing Commas

JSON does not allow an extra comma after the last item in an object or array. This is a common syntax mistake that causes parsing errors.

Wrong:
{
  "name": "John",
  "age": 30,
}

Correct:
{
  "name": "John",
  "age": 30
}
  

3. Including Comments

Unlike JavaScript, JSON does not allow comments. Beginners sometimes insert comments, thinking it's acceptable, but JSON parsers will throw an error.

Wrong:
// This is a comment
{ "name": "John" }
  

There should be no comments inside JSON files.

4. Incorrect Bracket Usage

Mixing up curly braces {} (objects) and square brackets [] (arrays) leads to invalid JSON structures. Always use the right symbols for the right data type.

5. Missing or Misplaced Colons and Commas

Colons separate keys and values; commas separate pairs. Beginners often misplace them, causing parsing failures.

Wrong:
{ "name" "John" }

Correct:
{ "name": "John" }
  

How to Avoid These Mistakes?

• Always use a JSON Validator before saving or deploying JSON.
• Use editors that highlight JSON errors automatically.
• Follow strict JSON syntax rules every time you edit or create a file.

Conclusion

Most JSON errors are simple to fix if you know where to look. By avoiding these beginner mistakes, you can work faster and build better applications. For more JSON tools and tips, explore Fshup's free online tools today!