# Create key (generate a key for encrypting the file(s))

The below code is implemented from[ here](https://developer.mozilla.org/en-US/docs/Web/API/SubtleCrypto/generateKey), where we create a[ CryptoKey](https://developer.mozilla.org/en-US/docs/Web/API/CryptoKey):

```javascript
 const key = await window.crypto.subtle.generateKey(
     {
       name: "AES-GCM",
       length: 256,
     },
     true,
     ["encrypt", "decrypt"]
   );

```

The appearance of the key in the application is extracted by the function:

```javascript
const readKey = await window.crypto.subtle.exportKey("jwk", key);
console.log(readKey.k);
```

This key will be used for encryption and decryption.  


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