Best Practices of API Authentication

Sat Jan 29 2022

3 min read

Authentication determines the client's identity who is sending the request and ensures that your API is adequately secured. With the rise of APIs, API security demands more focus than ever. This guide will highlight some good practices of API Authentication.

Let's take a look at API authentication.

API Authentication

You should always be aware of who is calling your APIs. Validating the clients of an API to identify if they are who they claim to be is called API authentication. Authentication allows you to restrict access to your API endpoint, which is essential for securing your API.

Moreover, authentication allows you to limit access to the API endpoints based on the requirements. We can also implement rate limits and audit logs through API authentication.

Best Practices

Here are some good practices to ensure robust API authentication.

Use API Keys

A suitable way to control access to your APIs is to use secret keys. With API key authentication, you can verify the identity of each app or user and mitigate the risks of unauthorized access. Moreover, this information can be used to maintain a log and determine the extent of resources accessed.

For example, RapidAPI Hub (which hosts thousands of public APIs) generates secret keys for implementing API Authentication that look like this.

Store API Keys Securely

API keys are very convenient to use, and they allow you to limit access to the API service. However, they do not identify the client's identity as anyone with the API key can access your service. Therefore, the client and the API provider must keep API keys secure to avoid them being compromised. A common mistake is embedding the API key in the code, which can be easily discovered. Instead, make a habit of using environment variables and secrets to store API keys.

Implement an Auth Standard

OAuth 2.0 (Open Authorization) is a standard developed to allow a user access to resources from a third-party application. It is an authorization protocol designed only to grant access to resources, and it works by using access tokens.

The access token is information that provides authorization to access resources on behalf of the user. Usually, the JSON Web Token (JWT) format is used for the access token. Implementing an Auth standard like OAuth 2.0 ensures proper authentication because the user's identity is validated, unlike API keys, where only the application's identity is validated.


API keys and authentication parameters may be compromised during server-client communication. Therefore, it is critical to use Transport layer Security(TLS) which protects the information by encrypting it. A quick way to check TLS availability is to see if the URL starts with https. If it does, then it means that TLS is enabled.

Final Note

That's pretty much it. We hope that this guide will help you keep the Authentication of your API in check.