What is a Unified API?

May 3, 2024

What is a Unified API?

A unified API is an API that brings together multiple APIs and presents them as a single API service. With a unified API, developers can integrate their applications with multiple SaaS applications using a single, consistent interface.

The purpose of a unified API is to simplify and streamline interactions for developers. By creating a layer of abstraction between an application and the APIs it uses, a unified API reduces the complexity and overhead associated with integrating data and functionality from different vendor platforms.

What are the Benefits of Using a Unified API?

Faster Development

Every integration with an API demands developer time and effort, from reviewing the documentation to experimental integrations to development to debugging and testing. Managing multiple APIs adds considerably to the time and effort developers must spend working with different authentication/authorization schemes, data representation and formatting, and error handling.

A unified API reduces the number of integrations and the amount of work associated with them, enabling developers to create new applications and services more quickly so they can get to market faster.

Reduced Complexity

Different APIs have different ways of representing the same concepts, even among APIs in the same vertical. For example, one API might refer to an end-user as a "User" while another would refer to them as a "Customer," and each representation may differ in their properties and the names for those properties.

A unified API offers a consistent approach for interacting with different services. This standardization means that developers can use the same methods to request and manipulate data, regardless of the underlying service or technology. Developers use a single set of tools for all their data needs instead of having multiple systems that need to be integrated and maintained separately.

Enhanced Functionality

Some APIs don't have features that would greatly simplify integrating with them. This forces developers to build workarounds, such as a polling system so that their application can be notified of updates to data, or a filtering system to limit the amount of data they receive from the API.

A well-designed unified API can function as a "wrapper" around APIs and enhance them by adding much-needed functionality that would otherwise be missing, such as webhooks to provide notifications for events and pagination for finer-grained control over the data received.

Increased Total Addressable Market

An application that can access different types of data has greater utility, which in turn leads to a larger market of potential customers.

A unified API with a large set of integrations acts a gateway to data from third-party vendors, which can expand an application's total addressable market and enlarge that application's potential user base.

What Should You Look for in a Unified API?

Abstraction and Unification

These are the primary reasons for using a unified API, so you should look for these features first.

API endpoints: A Unified API needs to have unified/common API endpoints for specific categories of integrations. That sounds obvious given the "Unified API" term, but most API solutions actually do not offer this. An API call to get a list of CRM contacts should be identical regardless of which integration that it is getting data from (e.g., Salesforce vs Hubspot).

Data models: Not only must API endpoints be unified, but the data models used by those APIs must be unified as well. A CRM contact object returned from Hubspot should have the same structure as a CRM contact object returned from Salesforce. The number of fields in those common/unified objects should be sufficient to satisfy most use cases.

Authorization: The method to authorize access to your customer's data in third-party vendors needs to be simple to use and unified for all integrations. Common information for the integration should be readily available so that your application can display it natively or the vendor should have an authentication widget.

Permission Scopes: Along with common/unified authentication, there should be a mechanism for abstracted permission scopes so that you do not need to research each vendor's OAuth2 scopes for your use cases.

Webhooks: Finally, while some vendors support webhooks, most do not. A unified API should abstract all of the complexities of handling those vendors that do not support webhooks and provide a unified webhook experience.

Ease of Implementation and Maintenance

After reviewing the features of a unified API, make sure that you have answers to these questions:

  • How quickly can you build a prototype using the unified API? How fast is it to scale that implementation in your production environment?
  • Does the unified API provide rich, detailed API Documentation? Do they have API explorers that allow you to test each of the APIs?
  • Do they support a modern, easy, and logical API endpoint path format that makes it easy to build and understand?
  • Will you need to handle any external connections to vendors that aren't handled by the unified API?
  • Will you need to rebuild or update your integration into the unified API vendor when a new version is released?


Security is a primary concern, especially when building an application with multiple integrations. Make sure that the unified API vendor that you choose has a good track record of keeping data safe and secure and has established security processes in place.

Ask these questions:

  • Do they encrypt their database, especially for OAuth2 client credentials (client ID and client secret)?
  • Do they store your customers' access tokens in an external secure external storage (e.g., AWS Secure Manager)?
  • Do they store any of your customers' third-party data at all or do they just have that data transit through their systems?


Your application relies on the unified API provider, so look for a company that has an SLA and process to notify its customers when something isn't right.

Ask these questions:

  • Where is the unified API hosted?
  • How has the unified API vendor scaled their system?
  • Does the unified API vendor know when a third-party vendor connection isn't working before your customer does?

Real-time information

When requesting information from a unified API, you want to ensure that you're getting the most current version in real time. You should ask if the information returned by the unified API…

  • …is being "stored-and-forwarded" to your application, or
  • …is being fetched in real-time, right at the moment your application requests it.


When your app becomes popular, then you'll need a unified API that can scale with demand. Otherwise, your users will have trouble accessing the service or worse, get frustrated with slow response times as usage increases.

Customization and Branding

Because a unified API vendor is providing an underlying technology for your application, their technology needs to be hidden from your users and provide them with a seamless, consistent user experience. Choose a vendor that allows you to use your own branding, including OAuth2 credentials.


To include a unified API vendor's technology within your own application, you need to be able to trust them, and they must be fully transparent with you.

They need to keep you apprised of:

  • Overall system uptime
  • Current errors in their system, and when they will be resolved
  • Which integrations are appropriate for your application's use case — and equally important: which ones aren't, so that you don't offer them to your customers and leave them disappointed

Use Case Compatibility

Not all unified API vendors are the same. Not all of them will support the use case that your application requires.

Some applications will want to only read in the name and email of a customer's Contacts in their CRM, but may need a large number of supported vendors in any one category (e.g., CRMs). The number of supported vendors in any one unified API category or overall is called breadth.

Other applications will require considerably more fields in the common data model. For example, an HR application may require additional information, such as the Employees' vacation history, date of birth, and years of tenure.

The number of fields supported in the common data model is called depth. The more complicated a use case is, the more depth it will require.

Does your application require more than one API category? For example, if you are building a customer monitoring application, you will want to synchronize with your customer's…

  • CRM,
  • Support ticketing,
  • Call Center, and
  • probably even Marketing Tech vendors…

all with the purpose of getting an accurate "picture" of your customer's customers.

Unified API vendors who support multiple vendor categories focus on clustering, the linking of several data models to a common object (in this case, a customer).

Pricing Models and Cost at Scale

Most unified API vendors have a free pricing tier, which allows you to try out their service. The more important pricing consideration is how much the unified API will cost as your application grows and scales.

Consider the following:

  • % of your selling price that will be taken by the cost of the unified API vendor
  • The pricing model — is it based on API usage, connections, or customers? How does it compare to your application's pricing model?

If you extrapolate out these two values on a graph or spreadsheet, you will clearly see if their pricing model fits your business model.

Check Out Unified.to for the Best Unified API for Your Use Case

We've built Unified.to with all of the above criteria in mind. We're offering the best in:

  • Real-time unified API, where every call you make brings you the most up-to-date data in real time,
  • Breadth — number of API vendors supported, with 160 and growing, and
  • Depth — number of common data fields provided by our data models…

…all while also delivering common API vendors that are in a common Cluster.

We've done this to support as many use cases for our customers as possible, while being very security conscious and taking your customers' data security concerns very seriously.

Let us know how we can better support you and your application's use case.