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# How to Capitalize a Word in JavaScript

Back to another round of Pictorials, where we solve popular algorithm challenges step-by-step with tidbits. Today, let's learn how to capitalize a word!

Here are the 4 methods I'll be covering:

☝️ Click more on the methods if you want to learn more. They're covered in my Web Basics series 👩🏻‍🏫

how to capitalize a string

# The Challenge

Write a function that capitalize a string.

how to capitalize a string 1

# 1. toLowerCase()

Unfortunately in JavaScript, there isn't a capitalize or title case a string. So what we can is utilize toLowerCase() to make the entire string lower-cased and then uppercase the first letter.

Convert the entire string to lower case.

how to capitalize a string 2

# 2. charAt()

Let's access the first letter of our string so we can uppercase it later.

Get the first character of the string

how to capitalize a string 3

# 3. toUpperCase()

Great! Now we can uppercase that first letter.

Transform the first character to upper case

how to capitalize a string 4

# 4. slice()

So there's 2 part of our string to complete our capitalization. The first letter which has been upper-cased and we got that with charAt(). Next we need the rest of our letters. And we can extract using .slice().

Extract the entire string except the first letter

how to capitalize a string 5

# 3. +

Alright, we have all the pieces. Next, we need to put it together. We can use our + operator to combine strings.

Combine the strings

how to capitalize a string 6

# Final Solution

Awesome! We have successfully capitalize our string 🥳

how to capitalize a string 7

# More Solutions

Using charAt

function capitalize(word) {
  const lower = str.toLowerCase();
  return str.charAt(0).toUpperCase() + lower.slice(1);

Using Bracket Notation

function capitalize(word) {
  return word[0].toUpperCase() + word.slice(1).toLowerCase();

Using substring

function capitalize(word) {
  return word[0].toUpperCase() + word.substring(1).toLowerCase();

Using 2 steps

function capitalize(word) {
  const loweredCase = word.toLowerCase();
  return word[0].toUpperCase() + loweredCase.slice(1);

Using Rest parameter

function capitalize([first, ...rest]) {
  return first.toUpperCase() + rest.join('').toLowerCase();

Using Map

function capitalize(word) {
  return word
    .map((letter, index) =>
      index ? letter.toLowerCase() : letter.toUpperCase(),

Using Regex

function capitalize(word) {
  return word.toLowerCase().replace(/\w/, firstLetter => firstLetter.toUpperCase());

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