<div class="container">
	<h2 class="title">Password Generator</h2>
	<div class="result">
		<div class="result__title field-title">Generated Password</div>
		<div class="result__info right">click to copy</div>
		<div class="result__info left">copied</div>
		<div class="result__viewbox" id="result">CLICK GENERATE</div>
		<button id="copy-btn" style="--x: 0; --y: 0"><i class="far fa-copy"></i></button>
	</div>
	<div class="length range__slider" data-min="4" data-max="32">
		<div class="length__title field-title" data-length='0'>length:</div>
		<input id="slider" type="range" min="4" max="32" value="16" />
	</div>

	<div class="settings">
		<span class="settings__title field-title">settings</span>
		<div class="setting">
			<input type="checkbox" id="uppercase" checked />
			<label for="uppercase">Include Uppercase</label>
		</div>
		<div class="setting">
			<input type="checkbox" id="lowercase" checked />
			<label for="lowercase">Include Lowercase</label>
		</div>
		<div class="setting">
			<input type="checkbox" id="number" checked />
			<label for="number">Include Numbers</label>
		</div>
		<div class="setting">
			<input type="checkbox" id="symbol" />
			<label for="symbol">Include Symbols</label>
		</div>
	</div>

	<button class="btn generate" id="generate">Generate Password</button>
</div>


<div class="support">
	<a href="https://twitter.com/DevLoop01" target="_blank"><i class="fab fa-twitter-square"></i></a>
	<a href="https://codepen.io/dev_loop/" target="_blank"><i class="fab fa-codepen"></i></a>
</div>

<a class="github-corner" href="https://github.com/devloop01/password-generator" title="Fork me on GitHub" target="_blank">
	<svg width="80" height="80" viewbox="0 0 250 250">
		<title>Fork me on GitHub</title>
		<path d="M0 0h250v250" />
		<path class="octo-arm" d="M127.4 110c-14.6-9.2-9.4-19.5-9.4-19.5 3-7 1.5-11 1.5-11-1-6.2 3-2 3-2 4 4.7 2 11 2 11-2.2 10.4 5 14.8 9 16.2" fill="currentColor" style="transform-origin:130px 110px;" />
		<path class="octo-body" d="M113.2 114.3s3.6 1.6 4.7.6l15-13.7c3-2.4 6-3 8.2-2.7-8-11.2-14-25 3-41 4.7-4.4 10.6-6.4 16.2-6.4.6-1.6 3.6-7.3 11.8-10.7 0 0 4.5 2.7 6.8 16.5 4.3 2.7 8.3 6 12 9.8 3.3 3.5 6.7 8 8.6 12.3 14 3 16.8 8 16.8 8-3.4 8-9.4 11-11.4 11 0 5.8-2.3 11-7.5 15.5-16.4 16-30 9-40 .2 0 3-1 7-5.2 11l-13.3 11c-1 1 .5 5.3.8 5z" fill="currentColor" />
	</svg>
</a>
* {
	margin: 0;
	padding: 0;
	box-sizing: border-box;
}
body {
	width: 100%;
	height: 100vh;
	background-image: linear-gradient(to top, #209cff 100%, #68e0cf 200%);
	display: flex;
	justify-content: center;
	align-items: center;
}
button {
	border: 0;
	outline: 0;
}

.container {
	margin: 40px 0;
	width: 400px;
	height: 600px;
	padding: 10px 25px;
	background: #0a0e31;
	border-radius: 10px;
	box-shadow: 0 0 5px rgba(0, 0, 0, 0.45), 0 4px 8px rgba(0, 0, 0, 0.35), 0 8px 12px rgba(0, 0, 0, 0.15);
	font-family: "Montserrat";
	h2.title {
		font-size: 1.75rem;
		margin: 10px -5px;
		margin-bottom: 30px;
		color: #fff;
	}
}

$field-color: rgba(255, 255, 255, 0.08);
$field-height: 65px;
$field-border-radius: 8px;

.result {
	position: relative;
	width: 100%;
	height: 65px;
	overflow: hidden;
	&__info {
		&.right {
			right: 8px;
		}
		&.left {
			left: 8px;
		}
		position: absolute;
		bottom: 4px;
		color: #fff;
		font-size: 0.8rem;
		transition: all 150ms ease-in-out;
		transform: translateY(200%);
		opacity: 0;
	}
	&__viewbox {
		width: 100%;
		height: 100%;
		background: $field-color;
		border-radius: $field-border-radius;
		color: #fff;
		text-align: center;
		line-height: 65px;
	}
	#copy-btn {
		position: absolute;
		top: var(--y);
		left: var(--x);
		width: 38px;
		height: 38px;
		background: #fff;
		border-radius: 50%;
		opacity: 0;
		transform: translate(-50%, -50%) scale(0);
		transition: all 350ms cubic-bezier(0.175, 0.885, 0.32, 1.275);
		cursor: pointer;
		z-index: 2;
		&:active {
			box-shadow: 0 0 0 200px rgba(255, 255, 255, 0.08);
		}
	}
	&:hover {
		#copy-btn {
			opacity: 1;
			transform: translate(-50%, -50%) scale(1.35);
		}
	}
}
.field-title {
	position: absolute;
	top: -10px;
	left: 8px;
	transform: translateY(-50%);
	font-weight: 800;
	color: rgba(255, 255, 255, 0.5);
	text-transform: uppercase;
	font-size: 0.65rem;
	pointer-events: none;
	user-select: none;
}

.options {
	width: 100%;
	height: auto;
	margin: 50px 0;
}
.range__slider {
	position: relative;
	width: 100%;
	height: calc(#{$field-height} - 10px);
display: flex;
justify-content: center;
align-items: center;
background: $field-color;
border-radius: $field-border-radius;
margin: 30px 0;

&::before,
&::after {
	position: absolute;
	color: #fff;
	font-size: 0.9rem;
	font-weight: bold;
}
&::before {
	content: attr(data-min);
	left: 10px;
}
&::after {
	content: attr(data-max);
	right: 10px;
}
.length__title::after {
	content: attr(data-length);
	position: absolute;
	right: -16px;
	font-variant-numeric: tabular-nums;
	color: #fff;
}
}

$range-handle-color: rgb(255, 255, 255) !default;
$range-handle-color-hover: rgb(212, 212, 212) !default;
$range-handle-size: 20px !default;

$range-track-color: rgba(255, 255, 255, 0.314) !default;
$range-track-height: 2px !default;

$range-label-width: 60px !default;

#slider {
	-webkit-appearance: none;
	width: calc(100% - (#{$range-label-width + 10px}));
	height: $range-track-height;
	border-radius: 5px;
	background: $range-track-color;
	outline: none;
	padding: 0;
	margin: 0;
	cursor: pointer;

	// Range Handle
	&::-webkit-slider-thumb {
		-webkit-appearance: none;
		width: $range-handle-size;
		height: $range-handle-size;
		border-radius: 50%;
		background: $range-handle-color;
		cursor: pointer;
		transition: all 0.15s ease-in-out;
		&:hover {
			background: $range-handle-color-hover;
			transform: scale(1.2);
		}
	}
	&::-moz-range-thumb {
		width: $range-handle-size;
		height: $range-handle-size;
		border: 0;
		border-radius: 50%;
		background: $range-handle-color;
		cursor: pointer;
		transition: background 0.15s ease-in-out;
		&:hover {
			background: $range-handle-color-hover;
		}
	}
}

.settings {
	position: relative;
	height: auto;
	widows: 100%;
	display: flex;
	flex-direction: column;

	.setting {
		position: relative;
		width: 100%;
		height: calc(#{$field-height} - 10px);
	background: $field-color;
	border-radius: $field-border-radius;
	display: flex;
	align-items: center;
	padding: 10px 25px;
	color: #fff;
	margin-bottom: 8px;
	input {
		opacity: 0;
		position: absolute;
		+ label {
			user-select: none;
			&::before,
			&::after {
				content: "";
				position: absolute;
				transition: 150ms cubic-bezier(0.24, 0, 0.5, 1);
				transform: translateY(-50%);
				top: 50%;
				right: 10px;
				cursor: pointer;
			}
			&::before {
				height: 30px;
				width: 50px;
				border-radius: 30px;
				background: rgba(214, 214, 214, 0.434);
			}
			&::after {
				height: 24px;
				width: 24px;
				border-radius: 60px;
				right: 32px;
				background: #fff;
			}
		}
		&:checked {
			& + label:before {
				background: #5d68e2;
				transition: all 150ms cubic-bezier(0, 0, 0, 0.1);
			}
			& + label:after {
				right: 14px;
			}
		}
		&:focus {
			+ label:before {
				box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.75);
			}
		}
		&:disabled{
			+ label{
				&:before, &:after{ cursor: not-allowed }
				&:before{ background: #4f4f6a }
				&:after{ background: #909090 }
			}
		}
	}
}
}

.btn.generate {
	user-select: none;
	position: relative;
	width: 100%;
	height: 50px;
	margin: 10px 0;
	border-radius: $field-border-radius;
	color: #fff;
	border: none;
	background-image: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
	letter-spacing: 1px;
	font-weight: bold;
	text-transform: uppercase;
	cursor: pointer;
	transition: all 150ms ease;
	&:active {
		transform: translateY(-3%);
		box-shadow: 0 4px 8px rgba(255, 255, 255, 0.08);
	}
}



.support{
	position: fixed;
	right: 10px;
	bottom: 10px;
	padding: 10px;
	display: flex;
}
a{
	margin: 0 20px;
	color: #fff;
	font-size: 2rem;
	transition: all 400ms ease;
}

a:hover{
	color: #222;
}

.github-corner svg{
	position:absolute;
	right:0;
	top:0;
	mix-blend-mode:darken;
	color:#eeeeee;
	fill:#353535;
	clip-path: polygon(0 0, 100% 0, 100% 100%);
}
.github-corner:hover .octo-arm{
	animation:octocat-wave .56s;
}
@keyframes octocat-wave{
	0%, 100%{
		transform:rotate(0);
	}
	20%, 60%{
		transform:rotate(-20deg);
	}
	40%, 80%{
		transform:rotate(10deg);
	}
}
View Compiled
// This is a simple Password Generator App that will generate random password maybe you can you them to secure your account.
// I tried my best to make the code as simple as possible please dont mind the variable names.
// Also this idea came in my mind after checking Traversy Media's latest video.

// Clear the concole on every refresh
console.clear();
// set the body to full height
// document.body.style.height = `${innerHeight}px`

// Range Slider Properties.
// Fill : The trailing color that you see when you drag the slider.
// background : Default Range Slider Background
const sliderProps = {
	fill: "#0B1EDF",
	background: "rgba(255, 255, 255, 0.214)",
};

// Selecting the Range Slider container which will effect the LENGTH property of the password.
const slider = document.querySelector(".range__slider");

// Text which will show the value of the range slider.
const sliderValue = document.querySelector(".length__title");

// Using Event Listener to apply the fill and also change the value of the text.
slider.querySelector("input").addEventListener("input", event => {
	sliderValue.setAttribute("data-length", event.target.value);
	applyFill(event.target);
});
// Selecting the range input and passing it in the applyFill func.
applyFill(slider.querySelector("input"));
// This function is responsible to create the trailing color and setting the fill.
function applyFill(slider) {
	const percentage = (100 * (slider.value - slider.min)) / (slider.max - slider.min);
	const bg = `linear-gradient(90deg, ${sliderProps.fill} ${percentage}%, ${sliderProps.background} ${percentage +
			0.1}%)`;
	slider.style.background = bg;
	sliderValue.setAttribute("data-length", slider.value);
}

// Object of all the function names that we will use to create random letters of password
const randomFunc = {
	lower: getRandomLower,
	upper: getRandomUpper,
	number: getRandomNumber,
	symbol: getRandomSymbol,
};

// Random more secure value
function secureMathRandom() {
	return window.crypto.getRandomValues(new Uint32Array(1))[0] / (Math.pow(2, 32) - 1);
}

// Generator Functions
// All the functions that are responsible to return a random value taht we will use to create password.
function getRandomLower() {
	return String.fromCharCode(Math.floor(Math.random() * 26) + 97);
}
function getRandomUpper() {
	return String.fromCharCode(Math.floor(Math.random() * 26) + 65);
}
function getRandomNumber() {
	return String.fromCharCode(Math.floor(secureMathRandom() * 10) + 48);
}
function getRandomSymbol() {
	const symbols = '~!@#$%^&*()_+{}":?><;.,';
	return symbols[Math.floor(Math.random() * symbols.length)];
}

// Selecting all the DOM Elements that are necessary -->

// The Viewbox where the result will be shown
const resultEl = document.getElementById("result");
// The input slider, will use to change the length of the password
const lengthEl = document.getElementById("slider");

// Checkboxes representing the options that is responsible to create differnt type of password based on user
const uppercaseEl = document.getElementById("uppercase");
const lowercaseEl = document.getElementById("lowercase");
const numberEl = document.getElementById("number");
const symbolEl = document.getElementById("symbol");

// Button to generate the password
const generateBtn = document.getElementById("generate");
// Button to copy the text
const copyBtn = document.getElementById("copy-btn");
// Result viewbox container
const resultContainer = document.querySelector(".result");
// Text info showed after generate button is clicked
const copyInfo = document.querySelector(".result__info.right");
// Text appear after copy button is clicked
const copiedInfo = document.querySelector(".result__info.left");

// if this variable is trye only then the copyBtn will appear, i.e. when the user first click generate the copyBth will interact.
let generatedPassword = false;

// Update Css Props of the COPY button
// Getting the bounds of the result viewbox container
let resultContainerBound = {
	left: resultContainer.getBoundingClientRect().left,
	top: resultContainer.getBoundingClientRect().top,
};
// This will update the position of the copy button based on mouse Position
resultContainer.addEventListener("mousemove", e => {
	resultContainerBound = {
		left: resultContainer.getBoundingClientRect().left,
		top: resultContainer.getBoundingClientRect().top,
	};
	if(generatedPassword){
		copyBtn.style.opacity = '1';
		copyBtn.style.pointerEvents = 'all';
		copyBtn.style.setProperty("--x", `${e.x - resultContainerBound.left}px`);
		copyBtn.style.setProperty("--y", `${e.y - resultContainerBound.top}px`);
	}else{
		copyBtn.style.opacity = '0';
		copyBtn.style.pointerEvents = 'none';
	}
});
window.addEventListener("resize", e => {
	resultContainerBound = {
		left: resultContainer.getBoundingClientRect().left,
		top: resultContainer.getBoundingClientRect().top,
	};
});

// Copy Password in clipboard
copyBtn.addEventListener("click", () => {
	const textarea = document.createElement("textarea");
	const password = resultEl.innerText;
	if (!password || password == "CLICK GENERATE") {
		return;
	}
	textarea.value = password;
	document.body.appendChild(textarea);
	textarea.select();
	document.execCommand("copy");
	textarea.remove();

	copyInfo.style.transform = "translateY(200%)";
	copyInfo.style.opacity = "0";
	copiedInfo.style.transform = "translateY(0%)";
	copiedInfo.style.opacity = "0.75";
});

// When Generate is clicked Password id generated.
generateBtn.addEventListener("click", () => {
	const length = +lengthEl.value;
	const hasLower = lowercaseEl.checked;
	const hasUpper = uppercaseEl.checked;
	const hasNumber = numberEl.checked;
	const hasSymbol = symbolEl.checked;
	generatedPassword = true;
	resultEl.innerText = generatePassword(length, hasLower, hasUpper, hasNumber, hasSymbol);
	copyInfo.style.transform = "translateY(0%)";
	copyInfo.style.opacity = "0.75";
	copiedInfo.style.transform = "translateY(200%)";
	copiedInfo.style.opacity = "0";
});

// Function responsible to generate password and then returning it.
function generatePassword(length, lower, upper, number, symbol) {
	let generatedPassword = "";
	const typesCount = lower + upper + number + symbol;
	const typesArr = [{ lower }, { upper }, { number }, { symbol }].filter(item => Object.values(item)[0]);
	if (typesCount === 0) {
		return "";
	}
	for (let i = 0; i < length; i++) {
		typesArr.forEach(type => {
			const funcName = Object.keys(type)[0];
			generatedPassword += randomFunc[funcName]();
		});
	}
	return generatedPassword.slice(0, length)
									.split('').sort(() => Math.random() - 0.5)
									.join('');
}

// function that handles the checkboxes state, so at least one needs to be selected. The last checkbox will be disabled.
function disableOnlyCheckbox(){
	let totalChecked = [uppercaseEl, lowercaseEl, numberEl, symbolEl].filter(el => el.checked)
	totalChecked.forEach(el => {
		if(totalChecked.length == 1){
			el.disabled = true;
		}else{
			el.disabled = false;
		}
	})
}

[uppercaseEl, lowercaseEl, numberEl, symbolEl].forEach(el => {
	el.addEventListener('click', () => {
		disableOnlyCheckbox()
	})
})

External CSS

  1. https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.11.2/css/all.min.css
  2. https://fonts.googleapis.com/css?family=Montserrat&amp;display=swap

External JavaScript

This Pen doesn't use any external JavaScript resources.