Express res.render() Function
Last Updated :
04 Apr, 2025
The res.render() function in Express.js is used to render a view template and send the resulting HTML to the client. This allows you to dynamically generate HTML pages by combining your templates with data.
Syntax:
res.render(view [, locals] [, callback]);
Parameters
- view (required): A string representing the file path of the view template to render.
- locals (optional): An object containing the data that will be passed to the view template. If a callback function is provided as the third argument, this parameter can be omitted or set to an empty object {}.
- callback (optional): A function that executes after the view has been rendered. It receives two arguments: err (an error object, if any) and renderedHtml (the rendered HTML string). If this function is not provided, Express will automatically send the rendered HTML to the client.
Returns: This function does not return a value. Instead, it sends the rendered HTML to the client as the response.
Now, let's discuss the steps to install the express module
Steps to Install the Express Module
Step 1: Installing the required modules
npm install express ejs
Step 2: After installing the express module, you can check your express version in the command prompt using the command.
npm version express
Project Structure:
Project StructureThe updated dependencies in package.json file will look like:
"dependencies": {
"ejs": "^3.1.9",
"express": "^4.18.2",
}Example 1: Below is the code of res.render() Function implementation.
HTML
<html>
<head>
<title>res.render() Demo</title>
</head>
<body>
<h2>Welcome to GeeksforGeeks</h2>
</body>
</html>
const express = require('express');
const app = express();
const PORT = 3000;
// View engine setup
app.set('view engine', 'ejs');
// Without middleware
app.get('/user', function (req, res) {
// Rendering home.ejs page
res.render('home');
})
app.listen(PORT, function (err) {
if (err) console.log(err);
console.log("Server listening on PORT", PORT);
});
Steps to run the program:
Run the index.js file using the below command:
node index.js
Console Output:
Server listening on PORT 3000
Browser Output:
Now open the browser and go to http://localhost:3000/user, you can see the following output on your screen:
Welcome to GeeksforGeeks
Example 2: Below is the code of res.render() Function implementation.
HTML
<html>
<head>
<title>res.render() Demo</title>
</head>
<body>
<h2>Render Function Demo</h2>
</body>
</html>
const express = require('express');
const app = express();
const PORT = 3000;
// View engine setup
app.set('view engine', 'ejs');
// With middleware
app.use('/', function (req, res, next) {
res.render('User')
next();
});
app.get('/', function (req, res) {
console.log("Render Working")
res.send();
});
app.listen(PORT, function (err) {
if (err) console.log(err);
console.log("Server listening on PORT", PORT);
});
Steps to run the program:
Run the index.js file using the below command:
node index.js
Console Output: After running the above command, you will see the following output on your console screen:
Server listening on PORT 3000
Render Working
Browser Output: Now open the browser and go to http://localhost:3000, you can see the following output on your screen:
Render Function Demo