Angular 21 Release Guide: Features, Benefits & How to Upgrade

Q: Is Angular 21 stable for production use?

Yes, Angular 21 is stable for production. Core features like zoneless change detection and Vitest testing are fully supported, while Signal Forms and Angular Aria are currently experimental or in preview.

Q: Do I need to remove zone.js when upgrading to Angular 21?

No. Angular 21 defaults to zoneless change detection for new projects, but existing apps can migrate gradually, continuing to use zone.js until fully ready.

Q: Will my existing tests work after upgrading?

Angular 21 introduces Vitest as the default test runner. Existing Karma/Jasmine tests can be migrated automatically using Angular schematics, though minor adjustments may be needed for full compatibility.

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ON THIS PAGE

The Most Important Updates in Angular 21
What to Know Before Switching to Angular 21
When you Should (and Shouldn’t) Switch to Angular 21
A Step-By-Step Guide for Switching to Angular 21
Getting Started with Angular 21

ON THIS PAGE

The Most Important Updates in Angular 21
What to Know Before Switching to Angular 21
When you Should (and Shouldn’t) Switch to Angular 21
A Step-By-Step Guide for Switching to Angular 21
Getting Started with Angular 21

Summary: Discover the future of web development with Angular 21. This blog dives into what’s new in Angular 21, highlights its key features, and offers a quick upgrade guide for developers ready to embrace modern, efficient workflows.

Angular, a widely-used framework maintained by Google since 2010, is evolving with its latest major release: Angular 21.

Major versions are typically released every six months. And as expected, 6 months after the previous version, Angular 20, came out in May 2025, Angular 21 was released on 20^th November 2025.

The latest update features zoneless change detection, the experimental Signal Forms API, AI-assisted tooling via the MCP server, and a modern testing workflow with Vitest.

With the release of v21, Angular is an even greater partner for your daily adventures — giving you the stability of the Angular framework while enabling you to build great AI-powered applications that are scalable and accessible for everyone.

— Jens Kuehlers & Mark “Techson” Thompson, Angular team at Google, wrote in a blog

At Radixweb, we have already started exploring Angular 21 for new projects. So, in this blog, we share insights, key updates, and guidance on adoption, illustrating how this release can influence your applications and workflow.

Let’s dive right in.

What is New in Angular 21: Most Important Features

The release of Angular 21 brings several transformative features that reshape the framework’s architecture, developer experience, and performance.

Below is a detailed look at what’s new in Angular 21.

1. Zoneless Change Detection

One of the most significant updates in Angular 21 is the move away from zone.js for automatic change detection. Instead, the framework now leverages signals, allowing components to update efficiently only when their reactive dependencies change. This leads to:

Faster runtime performance
Predictable, fine-grained change detection
Smaller bundle sizes

Example:

import { signal, effect } from '@angular/core';

const counter = signal(0);

// Automatically runs when counter changes
effect(() => {
console.log(`Counter value: ${counter()}`);
});
// Updating the signal triggers the effect
counter.set(counter() + 1);

This approach simplifies reactivity in Angular, reduces unnecessary DOM updates, and improves app performance.

2. Signal Forms (Experimental)

Signal Forms in Angular 21 are a new way to manage reactive forms using Angular’s signals. They are designed to reduce boilerplate, enhance type safety, and allow for more composable form logic compared to classic reactive or template-driven forms.

Example:

import { FormControl, toSignal } from '@angular/forms';

const nameControl = new FormControl('');
const nameSignal = toSignal(nameControl);

effect(() => {
console.log(`Name: ${nameSignal()}`);
});

nameControl.setValue('Radixweb');

Key benefits include of Signal Forms in Angular 21 include:

Real-time form state tracking via signals
Easier integration with components’ reactive state
Cleaner, more maintainable code

3. AI-Powered Tooling with MCP Server

Angular 21 introduces a Model Context Protocol (MCP) server in the CLI, enabling AI-assisted development. Features include:

Intelligent code suggestions
Automated migration assistance
Context-aware documentation

This improves developer productivity, particularly for teams upgrading older apps to Angular 21 or implementing complex reactive patterns.

4. Modern Testing with Vitest

Testing in Angular 21 has been modernized with Vitest as the default test runner for new projects. Compared to older Karma/Jasmine setups, Vitest offers:

Faster test execution
Built-in TypeScript support
A simplified API for unit and component tests

Example:

import { describe, it, expect } from 'vitest';
import { sum } from './math';

describe('sum function', () => {
it('should add two numbers correctly', () => {
expect(sum(2, 3)).toBe(5);
});
});

5. Angular Aria (Developer Preview)

Angular 21 introduces Angular Aria, a library of headless, accessibility-compliant components. With that, Angular developers can:

Use ARIA attributes effectively
Style components freely without breaking accessibility
Build more inclusive applications

Although in preview, Angular Aria lays the foundation for a more accessible Angular ecosystem.

6. HttpClient Provided by Default

In Angular 21, new projects include HttpClient by default, reducing setup steps and making HTTP communications easier:

import { HttpClient } from '@angular/common/http';
constructor(private http: HttpClient) {}

this.http.get('/api/data').subscribe(console.log);

7. Performance and Build Improvements

Angular 21 also brings:

Faster incremental builds
Improved SSR/hydration support
Optimized tree-shaking and bundle sizes

These enhancements make applications lighter, faster, and easier to maintain.

8. Developer Experience Enhancements

Beyond technical features, Angular 21 enhances the developer experience with:

Cleaner template patterns
Better type inference and error reporting
Smarter CLI commands and schematics

These improvements, combined with AI-assisted tooling, help developers adopt Angular 21 efficiently and build robust applications.

Overall, Angular 21 is a major leap forward. It streamlines development, improves performance, and prepares apps for the future. Developers can now leverage these features for faster, more maintainable, and accessible applications.

Learn about what’s new in Angular 21 straight from the Angular team:

Key Challenges and Considerations in Angular 21

While Angular 21 introduces powerful features and modernizes development workflows, it’s important for teams to be aware of certain considerations to ensure a smooth adoption. These points are not obstacles but rather areas to plan for when upgrading or starting new projects with Angular 21. Understanding them can help developers maximize benefits and avoid minor friction.

1. Experimental Signal Forms

The Signal Forms in Angular 21 feature is still considered experimental. While it offers type-safe, reactive form management and cleaner code, some advanced scenarios may require careful implementation. Developers can adopt it incrementally alongside existing reactive or template-driven forms without disrupting their applications.

2. Library and Third-Party Compatibility

As Angular 21 introduces zoneless change detection by default, certain third-party libraries or legacy packages might need updates to work seamlessly. Most popular libraries are already adopting Angular 21 compatibility, and the Angular ecosystem provides guidance for addressing minor integration issues. Planning for compatibility ensures a smooth transition.

3. Migration and Testing Updates

With Vitest replacing Karma/Jasmine as the default test runner, existing test suites may require adjustments. However, Angular 21 provides schematics and tools to automate much of this migration. The update presents an opportunity to modernize tests, improve speed, and align them with the framework’s future direction.

With proper awareness, teams can leverage Angular 21’s new features like zoneless reactivity, Signal Forms, and AI-powered tooling while maintaining stability and developer productivity.

Should You Switch to Angular 21?

Upgrading to the latest framework version and using the top Angular tools is generally beneficial, as it provides access to new features, improved performance, and long-term support. With Angular 21, developers can leverage zoneless change detection, Signal Forms, AI-assisted tooling, and modern testing with Vitest.

However, it is important to consider your project’s current state, dependencies, and readiness. To help, here’s a practical guide on when to switch and when you may choose to delay:

When to Switch to Angular 21	When You May Want to Delay the Upgrade
Your project can benefit from Signal Forms in Angular 21 for cleaner, type-safe form management.	Your project relies heavily on legacy libraries or third-party packages not yet fully compatible with Angular 21.
You want to adopt zoneless change detection and improved performance for more efficient updates.	Your current application is stable, and there’s minimal need for new features or performance improvements immediately.
You are starting a new project and want the latest developer experience, including AI-assisted tooling and Vitest testing.	Your team requires time to migrate existing Karma/Jasmine tests to Vitest or to familiarize themselves with new patterns.

By evaluating your project’s complexity, dependencies, and team readiness, you can decide the best time to adopt the latest release.

Don't think Angular 21 is the right for your new project? You can always consider Angular alternatives and choose a more suitable framework.

But if you are ready to make the switch, read on for a step-by-step Angular 21 upgrade guide.

How to Upgrade to Angular 21?

Upgrading to Angular 21 is simple if you approach it methodically. Here’s how to upgrade to Angular 21 with ease:

Step 1: Prepare your environment

Before upgrading, make sure your system meets Angular 21’s requirements:

Node.js – Use a supported version (e.g., Node 20+). Angular.schule
TypeScript – Update to the version Angular 21 expects (usually TS 5.x). angular.schule
Clean working tree – Commit or stash all changes in your git repo so the update runs smoothly.

Step 2. Check your current Angular version

Open a terminal in your project folder and run:

ng version

This tells you what Angular version you have now and what versions your dependencies are on. Angular

Step 3. Update the global Angular CLI (optional but recommended)

Updating the global CLI helps ensure you’re using the latest Angular tooling when running commands:

npm install -g @angular/cli@21

If you run into permission issues on macOS/Linux, you might need to use sudo.

Step 4. Run the update in your project

From your project root folder, run:

ng update @angular/core@21 @angular/cli@21

This CLI command:

Updates core Angular packages (@angular/core, @angular/common, etc.)
Updates the Angular CLI in your project
Applies auto-migrations for breaking changes where possible blog.codedthemes.com

Step 5. Update additional Angular packages

If you’re using other official Angular libraries (e.g., Angular Material, CDK), update those too:

ng update @angular/material@21 @angular/cdk@21

Many third-party Angular libraries also need compatible versions, so check them too.

Step 6. Review & fix breaking changes

Angular 21 introduces several major changes (like zoneless change detection default and Vitest replacing Karma). You might need to adjust code if:

You relied on Zone.js-dependent patterns
You used Karma/Jasmine test configs
Third-party libraries weren’t yet compatible with Angular 21 blog.codedthemes.com+1

Check your project by running:

npm run build
npm run test
npm run serve

Fix any errors or warnings before committing the upgrade.

Step 7. Test your full application

After the update:

Run your full test suite
Check UI behavior in the browser
Confirm build and deployment work as expected

This helps catch issues introduced by the upgrade.

What’s Next for Angular?The future of Angular continues to focus on signals-driven reactivity, enhanced performance, and developer productivity. With Angular 21 laying the foundation through zoneless change detection, Signal Forms, AI-assisted tooling, and modern testing workflows, we expect upcoming versions to further stabilize experimental features, expand accessibility support, and streamline development processes even more. Developers can anticipate smoother migrations, more robust third-party integrations, and continued alignment with modern web standards.At Radixweb, we specialize in Angular development and help businesses fully leverage the capabilities of Angular 21. Our team provides expert services ranging from upgrading existing applications to building scalable, high-performance web solutions from scratch. Whether you’re getting started with Angular 21 or exploring advanced features like Signal Forms and zoneless architecture, schedule a quick consultation with our Angular developers to get guidance on maximizing productivity, maintainability, and application performance.