Best unified API platforms to consider in 2025

Unified APIs offer a streamlined approach for integrating multiple external APIs through a single interface, which simplifies development and accelerates the integration process for AI agents or SaaS products. These platforms create universal data models for entities like "Employees" and "Companies," allowing for either shallow integrations or custom unified APIs to meet specific product needs. While pre-built unified APIs, such as those offered by Merge, Apideck, or Unified.to, are suitable for basic and broad integrations, they often lack the deep customization required for core product integrations. In contrast, platforms like Nango provide a customizable and code-driven approach, supporting over 500 APIs across various categories, which offers greater control and observability for complex use cases. However, building on platforms like Nango requires more upfront development and a steeper learning curve. The choice between pre-built and custom unified APIs should depend on the specific needs, capabilities, and goals of the development team, balancing the need for rapid deployment with the level of customization and functionality required.