btoa is a simple utility function that encodes a string in base-64 format. It is commonly used in web applications to encode data that needs to be safely transmitted over the internet, such as user credentials or binary data. While btoa is a straightforward solution for base-64 encoding, there are alternative libraries that offer similar functionality with additional features. Here are a couple of alternatives:

• base-64 is a lightweight library that provides base-64 encoding and decoding functions. It is designed to work in both browser and Node.js environments, making it versatile for various applications. base-64 is a good choice if you need a reliable and cross-platform solution for encoding and decoding base-64 strings, especially when working with different environments or when you require additional encoding options.
• js-base64 is another popular library for base-64 encoding and decoding in JavaScript. It offers a simple API and supports both browser and Node.js environments. In addition to standard base-64 encoding, js-base64 also provides URL-safe encoding options, which can be useful when working with data that needs to be included in URLs. If you are looking for a more feature-rich library that supports various encoding options, js-base64 is an excellent choice.

To see how btoa compares with base-64 and js-base64, check out the comparison: Comparing base-64 vs btoa vs js-base64.