Application programming interface keys are an essential part of using APIs. But what are they, exactly? API keys are authentication tokens in the form of unique strings of characters that allow you to access the data or web services an API offers. They act as a form of user authorization, proving that you are authorized to make requests to the API. In this article, we will discuss how API keys work and how you can use them to access the data offered by APIs.

DreamFactory Hosted Trial Signup

Generate a full-featured,documented, and secure REST API in minutes.

Sign up for our free 14 day hosted trial to learn how.

When to use API keys

API keys are unique identifiers that give developers a set of access rights for certain features or data of an application. For example, a developer may need a specific API key to access a database user interface or API server. Or an IoS or Android user may be looking to load a mobile app that draws data from Google Cloud. Keys are usually assigned by the web application owner and can be revoked at any time.

There are many different ways to use API keys, but the most common use cases include:

  • Restrict anonymous traffic: By requiring an API key, you can ensure that only authorized users access your data.
  • Rate limiting: You can use API keys to help control how much traffic your application can handle. You can prevent malicious use by attackers who attempt to overload your system with API calls. This is done by rate-limiting requests that include an API key.
  • Authentication: In some cases, API keys can be used as a form of authentication. For example, if you have a private API that requires user authentication, you may require each user to provide their API key to access the data. For businesses looking to increase security through authentication, consider using an integration platform like DreamFactory. DreamFactory allows you to integrate many different authentication APIs from different providers like Facebook, Salesforce, and Google with a few clicks of a button.
  • Data analysis: By tracking API keys, you can gain insights into how your application is being used. For example, you may see which users make the most requests or which API keys are associated with high-traffic applications.

The different types of API keys

There are two main types of API keys:

  • Public API keys: These are usually generated by the owner of the application and made available to developers or users. They allow developers to access public data or features of an application.
  • Private API keys: Private keys are used in server-to-server communications. They are typically used to authenticate requests or access data that is not publicly available. Private Keys should be kept secret and not shared with anyone.

Tips for using API keys

API keys are a great way to keep your data safe and secure. Here are a few tips for using them:

  • Avoid embedding API keys in code: Keys should be treated like passwords. They should never be hard-coded into your applications or committed to version control systems. If you must store them somewhere, use a secure location not accessible to the public.
  • Avoid storing API keys in the application source tree: If someone gains access to your source code, they will also be able to see any API keys that are hard-coded into your application. Instead, store API keys in a secure location outside the application source tree.
  • Use a different API key for each application: Each application that uses an API should have its own unique API key. This helps to ensure that if one application is compromised, the other applications will not be affected.
  • Rotate your API keys regularly: Just like passwords, it is essential to rotate and generate new keys regularly. This helps prevent attackers from using old keys that may have been compromised. For businesses looking to regularly generate new keys, consider using a platform like DreamFactory. DreamFactory allows users to generate and manage API keys easily.
  • Delete unused API keys: Keys that are no longer in use should be deleted to prevent them from being used by attackers. Unused keys may mistakenly be left in code posted online or in configuration files that are accidentally committed to version control.

Common errors when working with APIs and how to fix them

Errors can occur when working with APIs. Here are some of the most common ones and how to fix them:

  • Invalid API key: This error usually indicates that the API key is missing or incorrect. To fix this, check the documentation for the API to see what the requirements are for the API key. Ensure that you provide the correct key and that it is included in all API requests.
  • Missing required parameters: This error indicates that one or more of the required parameters is missing from the request. Parameters may consist of the API key, the format of the data, or the ID of the resource you are trying to access.
  • Rate limit exceeded: This error indicates that the API has been rate-limited. This means that too many requests have been made in a short period. To fix this, check the API documentation to see the rate limits and ensure you are not exceeding them. You may also need to wait for some time before making more requests.

Manage your API with DreamFactory

Implementing API keys is just one factor in creating and securing a high-quality API. API management platforms provide comprehensive security, scalability, and management features for businesses looking to build numerous APIs. DreamFactory is a complete API management platform that offers all of these features so that you can focus on building great APIs without worrying about the details.

Some of the top benefits of DreamFactory are:

Ease of use

DreamFactory is a RESTful API platform that can be set up by non-technical individuals with little or no IT knowledge. With a low code platform, you can quickly connect to any data source without having to write complex code. For more information on DreamFactory’s low code platform, check our page here


Compliance is a top concern for any business, and DreamFactory provides a secure platform with multiple layers of security. With features like user management, role-based access control, and API keys, you can ensure that your data is safe.

Unlimited API creation

With DreamFactory, there are no limits on the number of APIs you can create. This means that you can easily create APIs for all of your company’s data, no matter how many different data sources you have.

Fine-grained control over API access

API keys give you fine-grained control over which users and applications can access your data. You can easily revoke or regenerate a key if it is compromised without affecting other users or applications.

DreamFactory Hosted Trial Signup

Generate a full-featured,documented, and secure REST API in minutes.

Sign up for our free 14 day hosted trial to learn how.

Getting Started With DreamFactory

API keys are a necessary part of working with APIs. You can avoid common errors and build secure, scalable API solutions by understanding what they are and how to use them. DreamFactory is an excellent option for businesses that need to deploy and manage APIs at scale. With its simple platform and robust API security features, DreamFactory can help you focus on building outstanding apps without having to worry about the details. Start your free trial today.