Learn Netlify-functions - 10 Code Examples & CST Typing Practice Test

Netlify Functions is a serverless framework built into the Netlify platform, allowing developers to deploy AWS Lambda functions without managing infrastructure. It focuses on simplicity, fast deployment, and seamless integration with static sites and JAMstack apps.

View all 10 Netlify-functions code examples →

Simple Netlify Function (JavaScript)Netlify Function with Query Parameters Netlify Function with JSON Response Netlify Function with POST Body Netlify Function with Environment Variables Netlify Function Redirect Example Netlify Function Error Handling Netlify Function Delayed Response Netlify Function Fetch External API Netlify Function with Custom Headers

Learn NETLIFY-FUNCTIONS with Real Code Examples

Updated Nov 25, 2025

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Code Sample Descriptions

Simple Netlify Function (JavaScript)

# netlify/demo/hello.js
exports.handler = async function(event, context) {
    return {
        statusCode: 200,
        body: 'Hello, Netlify!'
    };
}

A simple Netlify Function responding with 'Hello, Netlify!' to HTTP requests.

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Netlify Function with Query Parameters

# netlify/demo/query.js
exports.handler = async function(event, context) {
    const name = event.queryStringParameters.name || 'Guest';
    return {
        statusCode: 200,
        body: `Hello, ${name}!`
    };
}

Reads query parameters and responds with a personalized message.

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Netlify Function with JSON Response

# netlify/demo/json.js
exports.handler = async function(event, context) {
    return {
        statusCode: 200,
        body: JSON.stringify({ message: 'Hello, JSON!' })
    };
}

Returns a JSON object in the response body.

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Netlify Function with POST Body

# netlify/demo/post.js
exports.handler = async function(event, context) {
    const data = JSON.parse(event.body || '{}');
    return {
        statusCode: 200,
        body: `Received: ${data.input}`
    };
}

Handles POST requests and parses JSON body.

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Netlify Function with Environment Variables

# netlify/demo/env.js
exports.handler = async function(event, context) {
    const secret = process.env.MY_SECRET || 'No Secret';
    return {
        statusCode: 200,
        body: `Secret is: ${secret}`
    };
}

Uses environment variables in the function.

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Netlify Function Redirect Example

# netlify/demo/redirect.js
exports.handler = async function(event, context) {
    return {
        statusCode: 302,
        headers: { 'Location': 'https://www.netlify.com/' },
        body: ''
    };
}

Responds with a redirect to another URL.

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Netlify Function Error Handling

# netlify/demo/error.js
exports.handler = async function(event, context) {
    try {
        throw new Error('Something went wrong');
    } catch(err) {
        return {
        statusCode: 500,
        body: err.message
        };
    }
}

Demonstrates returning an error response.

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Netlify Function Delayed Response

# netlify/demo/delay.js
exports.handler = async function(event, context) {
    await new Promise(resolve => setTimeout(resolve, 1000));
    return {
        statusCode: 200,
        body: 'Delayed Hello!'
    };
}

Returns a response after a simulated delay.

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Netlify Function Fetch External API

# netlify/demo/fetch.js
const fetch = require('node-fetch');
exports.handler = async function(event, context) {
    const res = await fetch('https://api.github.com');
    const data = await res.json();
    return {
        statusCode: 200,
        body: JSON.stringify(data)
    };
}

Fetches data from an external API and returns it.

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Netlify Function with Custom Headers

# netlify/demo/headers.js
exports.handler = async function(event, context) {
    return {
        statusCode: 200,
        headers: { 'X-Custom-Header': 'NetlifyFunction' },
        body: 'Hello with headers'
    };
}

Returns custom HTTP headers in the response.

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Frequently Asked Questions about Netlify-functions

What is Netlify-functions?

What are the primary use cases for Netlify-functions?

Adding serverless endpoints to static sites. Form submission handling. Custom API endpoints. Webhook listeners. Background tasks and scheduled jobs

What are the strengths of Netlify-functions?

No need to manage servers or containers. Fast deployment as part of site build. Automatic scaling to handle traffic spikes. Simple integration with JAMstack sites. Easy local testing and debugging

What are the limitations of Netlify-functions?

Limited execution time and memory (Lambda limits). Restricted to supported languages (JS/TS/Go). Vendor lock-in to Netlify platform. No built-in database; requires external services. Less suitable for complex backend architectures

How can I practice Netlify-functions typing speed?

CodeSpeedTest offers 10+ real Netlify-functions code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.

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Code Sample Descriptions

Simple Netlify Function (JavaScript)

# netlify/demo/hello.js
exports.handler = async function(event, context) {
    return {
        statusCode: 200,
        body: 'Hello, Netlify!'
    };
}

A simple Netlify Function responding with 'Hello, Netlify!' to HTTP requests.

Let’s Try →

Netlify Function with Query Parameters

# netlify/demo/query.js
exports.handler = async function(event, context) {
    const name = event.queryStringParameters.name || 'Guest';
    return {
        statusCode: 200,
        body: `Hello, ${name}!`
    };
}

Reads query parameters and responds with a personalized message.

Let’s Try →

Netlify Function with JSON Response

# netlify/demo/json.js
exports.handler = async function(event, context) {
    return {
        statusCode: 200,
        body: JSON.stringify({ message: 'Hello, JSON!' })
    };
}

Returns a JSON object in the response body.

Let’s Try →

Netlify Function with POST Body

# netlify/demo/post.js
exports.handler = async function(event, context) {
    const data = JSON.parse(event.body || '{}');
    return {
        statusCode: 200,
        body: `Received: ${data.input}`
    };
}

Handles POST requests and parses JSON body.

Let’s Try →

Netlify Function with Environment Variables

# netlify/demo/env.js
exports.handler = async function(event, context) {
    const secret = process.env.MY_SECRET || 'No Secret';
    return {
        statusCode: 200,
        body: `Secret is: ${secret}`
    };
}

Uses environment variables in the function.

Let’s Try →

Netlify Function Redirect Example

# netlify/demo/redirect.js
exports.handler = async function(event, context) {
    return {
        statusCode: 302,
        headers: { 'Location': 'https://www.netlify.com/' },
        body: ''
    };
}

Responds with a redirect to another URL.

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Netlify Function Error Handling

# netlify/demo/error.js
exports.handler = async function(event, context) {
    try {
        throw new Error('Something went wrong');
    } catch(err) {
        return {
        statusCode: 500,
        body: err.message
        };
    }
}

Demonstrates returning an error response.

Let’s Try →

Netlify Function Delayed Response

# netlify/demo/delay.js
exports.handler = async function(event, context) {
    await new Promise(resolve => setTimeout(resolve, 1000));
    return {
        statusCode: 200,
        body: 'Delayed Hello!'
    };
}

Returns a response after a simulated delay.

Let’s Try →

Netlify Function Fetch External API

# netlify/demo/fetch.js
const fetch = require('node-fetch');
exports.handler = async function(event, context) {
    const res = await fetch('https://api.github.com');
    const data = await res.json();
    return {
        statusCode: 200,
        body: JSON.stringify(data)
    };
}

Fetches data from an external API and returns it.

Let’s Try →

Netlify Function with Custom Headers

# netlify/demo/headers.js
exports.handler = async function(event, context) {
    return {
        statusCode: 200,
        headers: { 'X-Custom-Header': 'NetlifyFunction' },
        body: 'Hello with headers'
    };
}

Returns custom HTTP headers in the response.

Let’s Try →

Frequently Asked Questions about Netlify-functions

What is Netlify-functions?

What are the primary use cases for Netlify-functions?

Adding serverless endpoints to static sites. Form submission handling. Custom API endpoints. Webhook listeners. Background tasks and scheduled jobs

What are the strengths of Netlify-functions?

No need to manage servers or containers. Fast deployment as part of site build. Automatic scaling to handle traffic spikes. Simple integration with JAMstack sites. Easy local testing and debugging

What are the limitations of Netlify-functions?

How can I practice Netlify-functions typing speed?

CodeSpeedTest offers 10+ real Netlify-functions code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.