What Are Truthy and Falsy Values?

What Are Truthy and Falsy Values?

JavaScript automatically converts values into either true or false when evaluating conditions.

These values are known as:

• Truthy Values
• Falsy Values

Falsy Values

JavaScript has a small set of values that evaluate to false:

• false
• 0
• -0
• ""
• null
• undefined
• NaN

Example:

if (0) {
  console.log("Hello");
}

The code inside the block will not execute.

Truthy Values

Almost every other value is truthy.

Examples:

• "Hello"
• []
• {}
• 42
• "false"

Example:

if ("Hello") {
  console.log("Runs");
}

The condition evaluates to true.

Why Are Truthy and Falsy Values Important?

They are commonly used in:

• Conditional Statements
• Form Validation
• Default Values
• Short-Circuit Evaluation

Understanding them helps avoid bugs.

Common Interview Topic

Truthy and falsy values are frequently discussed during JavaScript interviews because they reveal how well a candidate understands type coercion.

The Bottom Line

Falsy values evaluate to false in conditions, while most other values are truthy. Understanding this behavior is essential for writing reliable JavaScript code.