Applicable for Angular 12

For projects that are running on the latest versions of Angular 12, you should be using TypeScript v4.2.x to 4.3.x

npm i -D typescript@4.3.5

Applicable for Angular 11

For projects that are running on the latest versions of Angular 11 (11.2.x), it supports up to TypeScript v4.1.5.

npm i -D typescript@4.1.5

Applicable for Angular 10 (as of June 2020)

For those who are using Angular 10, please note that TypeScript 3.9 must be installed, as the maintainers have removed support for TypeScript 3.8. The safest bet would be to install the latest version of TypeScript

npm i -D typescript@3.9.5

Applicable for Angular 9 (as of May 2020)

For projects that are running on the latest versions of Angular 9 (v9.1.x), it supports up to TypeScript v3.8.3. If you are using anything newer than that (such as TypeScript v3.9.0), you should downgrade it and install the supported versions:

npm i -D typescript@3.8.3

For projects that are running on the earlier versions of Angular 9 (v9.0.x), the supported TypeScript versions are TypeScript v3.6.5 to v3.7.5 (inclusive). Installing any other unsupported versions (such as 3.8.3) would result in an error similar to this:

ERROR in The Angular Compiler requires TypeScript >=3.6.4 and <3.8.0 but 3.8.3 was found instead

To fix it, you should install the supported versions stated on the error message. I would recommend you to install Typescript 3.7.x, as this will unlock useful features such as Optional Chaining and Nullish Coalescing.

npm i -D typescript@3.7.5

Alternatively, you can simply update Angular to the latest minor version (v9.1.x), as this should not contain any breaking changes.

Applicable for Angular 8 (Original Answer)

It seems like you have the latest version (v3.5.3) of TypeScript installed. You should be installing TypeScript v3.4.5 instead, which is the version that is supported by Angular 8.

You can try this command to install the specific version of TypeScript, rather than the latest version.

npm i -D typescript@3.4.5

In addition, you might want to consider changing the caret ^ for the TypeScript version on your package.json:

• Removing it completely means it will prevent npm from installing/using the most recent minor version (3.5.3).

  "typescript": "3.4.5"

• Changing it to "~" would tell npm that any patch release is acceptable

  "typescript": "~3.4.5" // will use latest version that matches 3.4.X

For more info about the use of the npm packages versioning: https://docs.npmjs.com/about-semantic-versioning

Applicable to those who are working on older Angular versions, such as Angular 2 to 7

|-----------------|--------------------|
| Angular version | TypeScript version |
|-----------------|--------------------|
|       6.1.x     |       3.6.x        |
|-----------------|--------------------|
|       7.2.x     |       2.9.x        |
|-----------------|--------------------|                                 

Likewise, if we are using any other Angular versions, you may install the respective TypeScript versions.

npm i -D typescript@3.6.4

Source - Refer to the full list of supported TypeScript versions for each Angular Version.

Additional useful information

There is actually a way to install TypeScript versions that are 'not supported' by the Angular version that is installed within your project, as pointed out by felipesilva. One benefit of doing so would be to allow you to install the latests versions of TypeScript (such as TypeScript 4.1.2 or any of the beta releases) on your project.

On your tsconfig.json, you can simply set disableTypeScriptVersionCheck as true.

{
  // ...
  "angularCompilerOptions": {
    // ...
    "disableTypeScriptVersionCheck": true
  }
}

However, do note that doing so is not recommended by the official Angular documentation:

Not recommended, as unsupported versions of TypeScript might have undefined behavior.

Please uninstall typescript by using the following command:

npm uninstall typescript

and then install typescript specific version:

npm i --save-dev typescript@3.4.5

This issue is mainly depended on @angular/cli version so typescript is depend on angular version

when you update angular check this website(devDependency)

https://david-dm.org/angular/angular-cli

and do

npm i --save-dev typescript@3.4.5

3.4.5version is required

Run this:

npm i --save-dev typescript@~3.4.5

Your wrong is "^" "typescript": "^3.4.0" in your package.json

the solution is "typescript": "~3.4.0"

Run this script to find exact version

npm install typescript@">=3.4.0 and <3.5.0" --save-dev

Good news!

You can use TypeScript 3.5 if you upgrade to Angular 8.2+. Version 8.1 didn't support it just yet.

Proof: https://github.com/angular/angular-cli/issues/15134#issuecomment-516908416

You don't need to uninstall and again install the typescript so you can install the specific version of typescript as recommended in the error.

npm install typescript@ version

or you can run

npm install typescript@ version --save-dev

to save it in the package json

I was getting this problem in my Angular 9 as well, but with different version numbers.

ERROR in The Angular Compiler requires TypeScript >=3.6.4 and <3.8.0 but 3.8.2 was found instead.

What I did was,

1. Went to the Angular 9 breaking changes
2. Searched for typescript version and found that it supports only 3.7
3. Edit my typescript version in package.json as "typescript": "~3.7.0"
4. ran npm i

The ~ here is important as it will make sure that it will update only to the next patch version (<3.8.0), not to the minor versions, if you use ^ it will update to minor versions too(for example, 4.0.0).

You have two options:

1-automatically:

this will install the right version

npm install typescript@">=3.4.0 and <3.5.0" --save-dev

2-manually:

go to package.json and change your typescript version, If you want to upgrade your angular project to

Angular 13 (npm install typescript@"~4.4.0" --save-dev)

"devDependencies": {
  ...
  "typescript": "~4.4.0"
}

Angular 12 (npm install typescript@"~4.2.0" --save-dev)

"devDependencies": {
  ...
  "typescript": "~4.2.0"
}

Angular 11 (npm install typescript@"~4.0.0" --save-dev)

"devDependencies": {
  ...
  "typescript": "~4.0.0"
}

Angular 10 (npm install typescript@"~3.8.0" --save-dev)

"devDependencies": {
  ...
  "typescript": "~3.8.0"
}

Angular 9 (npm install typescript@"~3.7.0" --save-dev)

"devDependencies": {
  ...
  "typescript": "~3.7.0"
}

Angular 8 (npm install typescript@"~3.4.0" --save-dev)

"devDependencies": {
  ...
  "typescript": "~3.4.0"
}

Angular 7 (npm install typescript@"~3.1.0" --save-dev)

"devDependencies": {
  ...
  "typescript": "~3.1.0"
}

Angular 6 (npm install typescript@"~2.9.0" --save-dev)

"devDependencies": {
  ...
  "typescript": "~2.9.0"
}

Angular 4 (npm install typescript@"~2.2.0" --save-dev)

"devDependencies": {
  ...
  "typescript": "~2.2.0"
}

Then run:

npm install 

use this command its work for me.. Thanks

npm i typescript@">=3.6.4 <3.8.0"

Instead of "typescript": "^3.4.5" under devDependencies in your package.json file enter "typescript": "~3.4.5" and save the file, then run npm install again. It worked for me.

Using Angular 11 use

npm i -D typescript@4.0.5

If you want to upgrade your angular project to Angular 11

npm install typescript@">=4.0.0 and <4.2.0" --save-dev

In package.json :

"devDependencies": {
      ...
      "typescript": "^4.1.5"
 }

In my case I received this error when migrating from Angular 10 to Angular 11.

An unhandled exception occurred: The Angular Compiler requires TypeScript >=4.0.0 and <4.2.0 but 4. 2.3 was found instead.

To resolve this issue I used this code in Visual Studio where my Angular project exist:

npm install typescript@'>==4.0.0 <4.2.0'

When I had a similar error, I run:

yarn clean cache

If you use npm you can try to run:

npm clean cache

I'm not sure that is a 100% solution, but I hope it can help someone.