Best LLM Routers for GPT-5.2 Thinking

OpenRouter is a unified AI inference platform that lets developers connect to a large catalog of models without integrating separately with every model provider. Through one API, users can access models from major AI companies including OpenAI, Google, Anthropic, Meta, Mistral, DeepSeek, Qwen, xAI, and numerous independent providers. The service supports multimodal workloads involving text, images, video, and audio. Developers can use a single account, credit balance, and API key across supported models instead of maintaining separate billing relationships and credentials. OpenRouter's routing infrastructure can prioritize providers based on factors such as price, latency, and reliability. Requests can also be redirected to alternate providers when a preferred endpoint becomes unavailable, helping applications maintain higher uptime. Organizations can configure data policies that restrict prompts to approved models and infrastructure providers. The platform provides benchmarks, model rankings, usage information, documentation, and developer tools for evaluating and deploying different models. OpenRouter is OpenAI API compatible, making it easier for teams to add broad model access to existing AI applications with limited integration changes.

FastRouter serves as a comprehensive API gateway designed to facilitate AI applications in accessing a variety of large language, image, and audio models (such as GPT-5, Claude 4 Opus, Gemini 2.5 Pro, and Grok 4) through a streamlined OpenAI-compatible endpoint. Its automatic routing capabilities intelligently select the best model for each request by considering important factors like cost, latency, and output quality, ensuring optimal performance. Additionally, FastRouter is built to handle extensive workloads without any imposed query per second limits, guaranteeing high availability through immediate failover options among different model providers. The platform also incorporates robust cost management and governance functionalities, allowing users to establish budgets, enforce rate limits, and designate model permissions for each API key or project. Real-time analytics are provided, offering insights into token utilization, request frequencies, and spending patterns. Furthermore, the integration process is remarkably straightforward; users simply need to replace their OpenAI base URL with FastRouter’s endpoint while configuring their preferences in the user-friendly dashboard, allowing the routing, optimization, and failover processes to operate seamlessly in the background. This ease of use, combined with powerful features, makes FastRouter an indispensable tool for developers seeking to maximize the efficiency of their AI applications.