How many extensions should I have installed?

There is no magic number, but 10 to 15 active extensions is a reasonable range for web development. Every extension adds memory usage and can slow down VS Code. Disable or uninstall extensions you are not actively using. You can disable extensions per-workspace if you only need them for certain projects.

Do extensions slow down VS Code?

Yes, some do. Extensions that scan your entire codebase (like some AI assistants or advanced IntelliSense tools) can noticeably slow things down on older machines. If VS Code feels sluggish, open the Command Palette, run "Developer: Show Running Extensions," and sort by activation time to find the culprits.

Should I use an AI coding extension?

AI coding assistants like GitHub Copilot can speed up experienced developers. For beginners, they can also short-circuit learning by writing code you do not understand. If you are learning, try writing code yourself first, then use an AI assistant to review what you wrote or explain concepts. Do not let it write entire functions you have not learned to write manually.

Best VS Code Extensions for Web Development

The essentials: install these first

These extensions belong in every web developer's setup. They solve real problems and do not conflict with each other.

Prettier. Auto-formats your code on save. Ends every argument about tabs vs spaces, semicolons vs no semicolons, and trailing commas. Install it, set it as your default formatter in settings, enable "Format on Save," and never think about formatting again.
ESLint. Catches bugs and bad patterns in your JavaScript and TypeScript before you run the code. It underlines problems directly in the editor. Pair it with Prettier by installing eslint-config-prettier so they do not fight.
GitLens. Shows who last edited each line, when it was changed, and the commit message. Invaluable when working on a team or trying to understand why code was written a certain way. The inline blame annotations are the killer feature.

Front-end extensions

Tailwind CSS IntelliSense. If you use Tailwind (and most new projects do), this extension gives you autocomplete for class names, hover previews of the generated CSS, and linting for conflicting classes. It turns Tailwind from "memorize hundreds of class names" into "type a few letters and pick from a list."
ES7+ React/Redux/React-Native snippets. Typing rafce and hitting Tab to generate a full React functional component saves time. Not life-changing, but a small quality-of-life improvement you will use daily.
Auto Rename Tag. Rename an opening HTML tag and the closing tag updates automatically. Simple, does one thing, does it well.

What about Emmet? It is built into VS Code already. You do not need an extension for it. Type div.container>ul>li*5 and hit Tab to generate the HTML structure.

Back-end and API extensions

REST Client. Send HTTP requests directly from a .http file in VS Code. No need to switch to Postman or Insomnia for simple API testing. Write your request, click "Send Request," and see the response in a split pane.
Thunder Client. If you prefer a GUI for API testing (more like Postman), Thunder Client gives you that inside VS Code. Use either this or REST Client, not both.
SQLite Viewer / Database Client. View your database tables directly in VS Code. Useful for SQLite during development or connecting to PostgreSQL/MySQL for quick queries.

Productivity

Error Lens. Shows error and warning messages inline at the end of the line where they occur, instead of making you hover over a red squiggle. You see the problem immediately without extra clicks.
Todo Tree. Scans your codebase for TODO, FIXME, and HACK comments and shows them in a tree view. Useful for tracking things you need to come back to.
Code Spell Checker. Catches typos in variable names, comments, and strings. Looks trivial until it saves you 30 minutes debugging a "uesrName" vs "userName" issue.

Extensions to skip

More extensions are not better. Each one adds startup time and potential conflicts. Skip these common recommendations:

Bracket colorizers. VS Code has native bracket pair colorization since 2021. Go to Settings, search "bracket pair," and enable it. No extension needed.
Path autocomplete extensions. VS Code handles path autocomplete natively for imports. Adding a third-party extension can actually cause duplicated suggestions.
Theme packs with 30 themes. Pick one theme you like and install just that one. One Dark Pro, GitHub Dark, or Catppuccin are solid choices. You do not need 30 themes you will never try.
Multiple formatters. Pick Prettier or Beautify, not both. Having two formatters causes unpredictable behavior on save.

A good rule: if you install an extension and do not notice it helping within a week, uninstall it.