Sometimes, we want to fix the ‘Index signature is missing in type’ error with TypeScript.

In this article, we’ll look at how to fix the ‘Index signature is missing in type’ error with TypeScript.

How to fix the ‘Index signature is missing in type’ error with TypeScript?

To fix the ‘Index signature is missing in type’ error with TypeScript, we can add an index signature to the interface causing the error.

For instance, we write

interface MyInterface {
  [key: string]: string;
  myVal: string;
}

to add [key: string]: string; to MyInterface.

This will let us add any property to the object with type MyInterface with a string key and value.

Conclusion

To fix the ‘Index signature is missing in type’ error with TypeScript, we can add an index signature to the interface causing the error.