How to Use AI Coding Tools to Create a Basic Web App in 2026

Building a web app might sound daunting, especially if you're just starting out as a solo founder or indie hacker. But what if I told you that with the right AI coding tools, you can whip up a basic web app in just 2 hours? That's right—this isn’t just theory; I've done it, and I'm here to share exactly how you can do it too.

Prerequisites: What You Need to Get Started

Before diving in, let’s ensure you have everything you need:

• Basic understanding of HTML, CSS, and JavaScript: You don’t need to be an expert, but familiarity with these languages will help.
• An AI coding tool: We'll discuss several options below, but for this demo, I'll be using OpenAI's Codex.
• A code editor: I recommend Visual Studio Code (VS Code) for its excellent support for extensions and ease of use.
• Node.js installed: This is essential if you want to run your web app locally. You can download it from nodejs.org.

Step 1: Choose Your AI Coding Tool

Here’s a quick table comparing a few popular AI coding tools that can help you in your web app development journey:

| Tool | Pricing | Best For | Limitations | Our Take | |---------------------|-----------------------------|------------------------------|-------------------------------------|----------------------------------| | OpenAI Codex | $0-20/mo for individual use | Generating code snippets | Limited context for complex apps | We use this for quick prototypes | | GitHub Copilot | $10/mo | Autocompleting code | Requires GitHub integration | Great for enhancing productivity | | Tabnine | Free tier + $12/mo pro | Code suggestions | Limited to supported languages | We don’t use this because it lacks context | | Replit | Free tier + $7/mo pro | Collaborative coding | Limited features in free tier | We use this for quick testing | | Codeium | Free | AI pair programming | Fewer integrations than others | We haven't tried this yet |

Step 2: Set Up Your Development Environment

1. Install VS Code: Download and install it from code.visualstudio.com.
2. Set up Node.js: After installation, verify it by running node -v in your terminal.
3. Create a new project folder: Open your terminal and run:

   mkdir my-web-app
   cd my-web-app
   npm init -y
   

Step 3: Generate Your App’s Basic Structure

Using OpenAI Codex, you can generate the basic HTML, CSS, and JavaScript files to kickstart your app. Here’s how to do it:

1. Open your code editor and create three files: index.html, styles.css, and app.js.
2. Use Codex to generate code: In your editor, type a prompt like:

   Create a simple HTML file for a web app with a title and a button that changes text when clicked.
   

3. Copy the generated code into your index.html file.

Example Output for index.html:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="styles.css">
    <title>My Web App</title>
</head>
<body>
    <h1>Welcome to My Web App!</h1>
    <button id="changeTextBtn">Click Me!</button>
    <script src="app.js"></script>
</body>
</html>

Step 4: Style Your App

Next, you can ask Codex to help with your CSS. A prompt like:

Generate CSS for a button that changes color on hover.

This should yield something like:

Example Output for styles.css:

body {
    font-family: Arial, sans-serif;
    text-align: center;
}

button {
    background-color: #4CAF50;
    color: white;
    border: none;
    padding: 15px 32px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 4px 2px;
    cursor: pointer;
}

button:hover {
    background-color: #45a049;
}

Step 5: Add Functionality

For the JavaScript part, ask Codex to create a function that changes the button text when clicked:

Create a JavaScript function that changes the button text to "You clicked me!" when clicked.

Example Output for app.js:

document.getElementById("changeTextBtn").addEventListener("click", function() {
    this.innerText = "You clicked me!";
});

Troubleshooting: Common Issues

• Code not running? Ensure you have a local server running. You can use the Live Server extension in VS Code to view your app.
• Errors in console? Double-check the console for error messages; it often points to the line where the problem is.

What's Next: Expand Your App

Once you have the basics down, consider adding more features like:

• User authentication: Use Firebase for a quick setup.
• Database integration: Use MongoDB Atlas for cloud databases.
• Styling frameworks: Consider Tailwind CSS for better design.

Conclusion: Start Here

Using AI coding tools, building a basic web app in 2 hours is not just possible; it’s straightforward. Start with OpenAI Codex or GitHub Copilot, follow the steps above, and you’ll have a working prototype in no time.

If you're looking to take your web app further, consider listening to our podcast, Built This Week, where we share tools, tips, and lessons from our own building journey.