Home Web Development JavaScript JavaScript Snake Game | Simple JavaScript Game Source Code

JavaScript Snake Game | Simple JavaScript Game Source Code

March 28, 2019

49042

Simple JavaScript Game with Source Code: You have no idea what you can do with javascript. JavaScript is one of the most demanding programming languages right now, there are so many libraries of JavaScript. So, There is a snake game built with JavaScript, HTML & CSS little bit. This is a very basic program. This snake game is like the legend game came with a Nokia Keypad phones.

You can call this a coding game or game with coding. In other words, this is javascript coding game. When I was learning web development, always I asked my instructor how can I create games in javascript. Now I am able to create very small programs in javascript. I am still learning, & And as much as I know, I share with you all. Because I believe sharing knowledge is the best way to increase knowledge.

Let’s come to our topic, How to make a basic snake game in javascript? The answer is in the form of source code. First, you must have good knowledge of HTML canvas, CSS & Javascript. Then you can understand this program easily.

Requirement For Create Snake Game

Knowledge of HTML.
Basic Knowledge Of CSS.
Good knowledge of JavaScript.
An IDE or notepad++

Note: If you don’t have knowledge in javascript, Then first learn. If you are learning javascript or want to learn, this demo also will be useful for you for the understanding the whole program.

Preview:

Let’s see a review of this game in GIF format.

javascript snake game code

JavaScript Snake Game Source Code

I have created just one file for this program because this program is small in length and size. I used little bit CSS, that’s why I put CSS in between <head> tag. Create an HTML file named “snakegame.html” or any name you want. Copy codes form here below and paste on HTML file.

<!doctype html>
<!--Code By WebDevTrick (https://webdevtrick.com)-->
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Simple JavaScript Snake Game| Webdevtrick.com</title>
	
	<style>
	canvas {
		display: block;
		position: absolute;
		border: 5px solid  #009BFF;
		margin: auto;
		top: 0;
		bottom: 0;
		right: 0;
		left: 0;
	}
	</style>
</head>
<body>
<script>
var
COLS = 26,
ROWS = 26,
EMPTY = 0,
SNAKE = 1,
FRUIT = 2,
LEFT  = 0,
UP    = 1,
RIGHT = 2,
DOWN  = 3,
KEY_LEFT  = 37,
KEY_UP    = 38,
KEY_RIGHT = 39,
KEY_DOWN  = 40,
canvas,	  
ctx,	  
keystate, 
frames,   
score;	  

grid = {

	width: null,  
	height: null, 
	_grid: null,  

	
	init: function(d, c, r) {
		this.width = c;
		this.height = r;

		this._grid = [];
		for (var x=0; x < c; x++) {
			this._grid.push([]);
			for (var y=0; y < r; y++) {
				this._grid[x].push(d);
			}
		}
	},

	
	set: function(val, x, y) {
		this._grid[x][y] = val;
	},

	
	get: function(x, y) {
		return this._grid[x][y];
	}
}


snake = {

	direction: null, 
	last: null,		 
	_queue: null,	

	
	init: function(d, x, y) {
		this.direction = d;

		this._queue = [];
		this.insert(x, y);
	},

	
	insert: function(x, y) {
		
		this._queue.unshift({x:x, y:y});
		this.last = this._queue[0];
	},

	
	remove: function() {
		
		return this._queue.pop();
	}
};


function setFood() {
	var empty = [];
	
	for (var x=0; x < grid.width; x++) {
		for (var y=0; y < grid.height; y++) {
			if (grid.get(x, y) === EMPTY) {
				empty.push({x:x, y:y});
			}
		}
	}
	
	var randpos = empty[Math.round(Math.random()*(empty.length - 1))];
	grid.set(FRUIT, randpos.x, randpos.y);
}


function main() {
	
	canvas = document.createElement("canvas");
	canvas.width = COLS*20;
	canvas.height = ROWS*20;
	ctx = canvas.getContext("2d");
	
	document.body.appendChild(canvas);

	
	ctx.font = "12px Helvetica";

	frames = 0;
	keystate = {};
	
	document.addEventListener("keydown", function(evt) {
		keystate[evt.keyCode] = true;
	});
	document.addEventListener("keyup", function(evt) {
		delete keystate[evt.keyCode];
	});

	
	init();
	loop();
}


function init() {
	score = 0;

	grid.init(EMPTY, COLS, ROWS);

	var sp = {x:Math.floor(COLS/2), y:ROWS-1};
	snake.init(UP, sp.x, sp.y);
	grid.set(SNAKE, sp.x, sp.y);

	setFood();
}


function loop() {
	update();
	draw();
	
	window.requestAnimationFrame(loop, canvas);
}


function update() {
	frames++;

	
	if (keystate[KEY_LEFT] && snake.direction !== RIGHT) {
		snake.direction = LEFT;
	}
	if (keystate[KEY_UP] && snake.direction !== DOWN) {
		snake.direction = UP;
	}
	if (keystate[KEY_RIGHT] && snake.direction !== LEFT) {
		snake.direction = RIGHT;
	}
	if (keystate[KEY_DOWN] && snake.direction !== UP) {
		snake.direction = DOWN;
	}

	
	if (frames%7 === 0) {
		
		var nx = snake.last.x;
		var ny = snake.last.y;

		
		switch (snake.direction) {
			case LEFT:
				nx--;
				break;
			case UP:
				ny--;
				break;
			case RIGHT:
				nx++;
				break;
			case DOWN:
				ny++;
				break;
		}

		
		if (0 > nx || nx > grid.width-1  ||
			0 > ny || ny > grid.height-1 ||
			grid.get(nx, ny) === SNAKE
		) {
			return init();
		}

		if (grid.get(nx, ny) === FRUIT) {
			
			score++;
			setFood();
		} else {
			
			var tail = snake.remove();
			grid.set(EMPTY, tail.x, tail.y);
		}

		grid.set(SNAKE, nx, ny);
		snake.insert(nx, ny);
	}
}


function draw() {
	
	var tw = canvas.width/grid.width;
	var th = canvas.height/grid.height;
	
	for (var x=0; x < grid.width; x++) {
		for (var y=0; y < grid.height; y++) {
			
			switch (grid.get(x, y)) {
				case EMPTY:
					ctx.fillStyle = "#fff";
					break;
				case SNAKE:
					ctx.fillStyle = "#333";
					break;
				case FRUIT:
					ctx.fillStyle = "#009BFF";
					break;
			}
			ctx.fillRect(x*tw, y*th, tw, th);
		}
	}
	
	ctx.fillStyle = "#000";
	ctx.fillText("SCORE: " + score, 10, canvas.height-10);
}


main();
</script>
</body>
</html>

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

<!doctype html>

<head>

<title>Simple JavaScript Snake Game| Webdevtrick.com</title>

<style>

canvas {

display: block;

position: absolute;

border: 5px solid #009BFF;

margin: auto;

top: 0;

bottom: 0;

right: 0;

left: 0;

}

</style>

</head>

<body>

var

COLS = 26,

ROWS = 26,

EMPTY = 0,

SNAKE = 1,

FRUIT = 2,

LEFT = 0,

UP = 1,

RIGHT = 2,

DOWN = 3,

KEY_LEFT = 37,

KEY_UP = 38,

KEY_RIGHT = 39,

KEY_DOWN = 40,

canvas,

ctx,

keystate,

frames,

score;

grid = {

width: null,

height: null,

_grid: null,

init: function(d, c, r) {

this.width = c;

this.height = r;

this._grid = [];

for (var x=0; x < c; x++) {

this._grid.push([]);

for (var y=0; y < r; y++) {

this._grid[x].push(d);

}

set: function(val, x, y) {

this._grid[x][y] = val;

get: function(x, y) {

return this._grid[x][y];

}

snake = {

direction: null,

last: null,

_queue: null,

init: function(d, x, y) {

this.direction = d;

this._queue = [];

this.insert(x, y);

insert: function(x, y) {

this._queue.unshift({x:x, y:y});

this.last = this._queue[0];

remove: function() {

return this._queue.pop();

}

};

function setFood() {

var empty = [];

for (var x=0; x < grid.width; x++) {

for (var y=0; y < grid.height; y++) {

if (grid.get(x, y) === EMPTY) {

empty.push({x:x, y:y});

}

var randpos = empty[Math.round(Math.random()*(empty.length - 1))];

grid.set(FRUIT, randpos.x, randpos.y);

}

function main() {

canvas = document.createElement("canvas");

canvas.width = COLS*20;

canvas.height = ROWS*20;

ctx = canvas.getContext("2d");

document.body.appendChild(canvas);

ctx.font = "12px Helvetica";

frames = 0;

keystate = {};

document.addEventListener("keydown", function(evt) {

keystate[evt.keyCode] = true;

});

document.addEventListener("keyup", function(evt) {

delete keystate[evt.keyCode];

});

init();

loop();

}

function init() {

score = 0;

grid.init(EMPTY, COLS, ROWS);

var sp = {x:Math.floor(COLS/2), y:ROWS-1};

snake.init(UP, sp.x, sp.y);

grid.set(SNAKE, sp.x, sp.y);

setFood();

}

function loop() {

update();

draw();

window.requestAnimationFrame(loop, canvas);

}

function update() {

frames++;

if (keystate[KEY_LEFT] && snake.direction !== RIGHT) {

snake.direction = LEFT;

}

if (keystate[KEY_UP] && snake.direction !== DOWN) {

snake.direction = UP;

}

if (keystate[KEY_RIGHT] && snake.direction !== LEFT) {

snake.direction = RIGHT;

}

if (keystate[KEY_DOWN] && snake.direction !== UP) {

snake.direction = DOWN;

}

if (frames%7 === 0) {

var nx = snake.last.x;

var ny = snake.last.y;

switch (snake.direction) {

case LEFT:

nx--;

break;

case UP:

ny--;

break;

case RIGHT:

nx++;

break;

case DOWN:

ny++;

break;

}

if (0 > nx || nx > grid.width-1 ||

0 > ny || ny > grid.height-1 ||

grid.get(nx, ny) === SNAKE

) {

return init();

}

if (grid.get(nx, ny) === FRUIT) {

score++;

setFood();

} else {

var tail = snake.remove();

grid.set(EMPTY, tail.x, tail.y);

}

grid.set(SNAKE, nx, ny);

snake.insert(nx, ny);

}

function draw() {

var tw = canvas.width/grid.width;

var th = canvas.height/grid.height;

for (var x=0; x < grid.width; x++) {

for (var y=0; y < grid.height; y++) {

switch (grid.get(x, y)) {

case EMPTY:

ctx.fillStyle = "#fff";

break;

case SNAKE:

ctx.fillStyle = "#333";

break;

case FRUIT:

ctx.fillStyle = "#009BFF";

break;

}

ctx.fillRect(x*tw, y*th, tw, th);

}

ctx.fillStyle = "#000";

ctx.fillText("SCORE: " + score, 10, canvas.height-10);

}

main();

</script>

</body>

</html>

That’s it. You have successfully created a snake game. If you have any doubt comment down below.
Thanks For Visiting, Keep Visiting.

12 COMMENTS

Aarav August 21, 2020 At 3:44 pm

HI! I want to do something fun with this game which is when you eat a blue apple I want them to get 10 bigger, not 1.

Reply
Mason September 5, 2020 At 5:28 am

What code compiler do I need to run the code because when I hit run I have to choose a program.

Reply
- hihihihihihi November 17, 2020 At 12:31 pm
  
  same I was using p5
  
  Reply
  - wdf June 10, 2021 At 3:51 am
    
    I also
    using the p5
    
    Reply
- zeythen February 15, 2021 At 4:35 pm
  
  seriously you just have to change code a bit
  and make your own i dident copy past it i only take some idea
  make your own don’t ask form dev- ok
  
  Reply
  - Anonymous February 24, 2021 At 2:27 pm
    
    sorry how do i add pause button
    
    Reply
Anonymous February 23, 2021 At 4:56 pm

Thanks for the code
Please how do i add pause and play button?

Reply
me January 24, 2022 At 3:24 pm

PURE 100% LIES I TRIED IT ITS PURE LIES LIES
█░░ █ █▀▀ █▀ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █ █
█▄▄ █ ██▄ ▄█ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

ₜᵢₙᵧ ₜₑₓₜ ᵦᵤₜ ₛₜᵢₗₗ ₗᵢₑₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛₛ!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Reply
- Anonymous August 15, 2022 At 9:54 pm
  
  Try putting it in a .html file. it’s in HTML with JavaScript in the HTML. That’s how HTML works, but you don’t seem bright enough to know that.
  
  Reply
- Moussa December 20, 2022 At 1:21 pm
  
  It works it is just that it doesn’t work for you.
  
  Reply
  - Moussa September 7, 2023 At 10:44 pm
    
    YOOO WE HAVE THE SAME NAME SPELT THE SAME
    
    Reply
sasas April 14, 2023 At 10:48 pm

I didn’t know how to download it soooooooooooooooooooooooooooooooooooo.

Reply