Best TensorZero Alternatives

Drop-in OpenAI-compatible proxy supporting 100+ LLM providers with load balancing, spend tracking, rate limiting, and fallback routing. Acts as a unified gateway for all your AI model calls, letting teams switch between providers, enforce budgets, and add reliability layers without changing application code. Essential infrastructure for multi-model AI architectures.

Portkey is an AI gateway and observability platform providing a unified API for 200+ LLM providers with intelligent routing, caching, rate limiting, and guardrails. Route requests across OpenAI, Anthropic, Google, and more with automatic failover, load balancing, and cost optimization. Features request logging, prompt management, evaluation tools, and real-time monitoring. The open-source gateway can be self-hosted; Portkey Cloud adds managed observability and team features.

Helicone is an open-source LLM observability and AI gateway platform with proxy-based request logging, cost tracking, latency monitoring, caching, rate limits, user analytics, prompt tools, and HQL. It supports OpenAI, Anthropic, Azure, LiteLLM, Anyscale, Together AI, and OpenRouter integrations, and now presents itself as part of Mintlify while continuing managed and self-hosted gateway/observability workflows.

Unified API gateway providing access to 500+ AI models from leading providers through a single OpenAI-compatible interface. OpenRouter eliminates the need to manage separate keys, billing, and integrations across providers like OpenAI, Anthropic, Google, and Meta, with built-in plugins for web search, PDF processing, automatic fallback routing, and per-model cost tracking.