Convert a Number to a String in TypeScript

# Convert a Number to a String in TypeScript

Use the String() constructor to convert a number to a string in TypeScript.

The String() constructor converts the supplied value to a string and returns the result.

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const num = 100;

// 👇️ const str: string
const str = String(num);

console.log(str); // 👉️ "100"
console.log(typeof str); // 👉️ "string"

We used the String() constructor to convert a number to a string in TypeScript.

The only parameter the function takes is the value that will be converted to a string.

# Converting a negative number to a string

If you convert a negative number to a string, the sign is preserved.

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const num = -100;

const str = String(num);

console.log(str); // 👉️ "-100"
console.log(typeof str); // 👉️ "string"

# Converting a floating-point number to a string

If you pass a number with a decimal to the String() constructor, the decimal is preserved.

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const num = 14.5;

const str = String(num);
console.log(str); // 👉️ "14.5"

# Convert a Number to a String using the toString() method

You can also use the Number.toString method to convert a number to a string in TypeScript.

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const num = 100;

const str = num.toString();

console.log(str); // 👉️ "100"
console.log(typeof str); // 👉️ "string"

The Number.toString() method returns a string representing the specified number.

However, note that you can't directly call a method on a number.

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// ⛔️ Error
const str = 100.toString();

The example shows how trying to call a built-in method on a number throws an error.

# Wrap the number in parentheses before calling toString()

You can wrap the number in parentheses before calling the toString() built-in method.

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const str = (100).toString();

console.log(str); // 👉️ "100"
console.log(typeof str); // 👉️ "string"

When using the Number.toString() method, the sign is also preserved after the conversion.

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const str = (-100).toString();

console.log(str); // 👉️ "-100"
console.log(typeof str); // 👉️ "string"

Which approach you pick is a matter of personal preference. I prefer using the String() constructor as it is more widely used in the codebases I've worked on.

If you need to convert a string to a number, check out the following article.

# Additional Resources

You can learn more about the related topics by checking out the following tutorials:

• How to Convert an Object to an Array in TypeScript
• How to convert an Object to a JSON string in Typescript
• Convert a String to a Boolean and vice versa in TypeScript
• How to convert a String to a Date object in TypeScript
• How to convert a String to Enum in TypeScript