The character limit applies to your data after it’s been encrypted. Our encryption algorithm increases the length of your data, so 9,000 characters unencrypted will exceed the 10,000 limit after encryption. It seems you can use 7,500 characters as an approximate limit for unencrypted text - see the recent discussion here: The field Notes exceeds the maximum encrypted value length of 10000 characters (when it is false) · Issue #1618 · bitwarden/browser · GitHub