AI gateway providers put a single API in front of multiple LLM providers, handling model routing, fallback, caching, rate limiting, cost controls, and access management in one place.
The right one depends on whether you need routing alone or routing with observability and evals built in, and that tradeoff separates most of the best LLM gateways in 2026.
19 tools compared · Layer 1 · Updated October 13, 2026
Ranked by community traction, recent activity, and popularity.
Respan
One API for 1,000+ models
Respan is the AI router with built-in observability and automated evals, built for teams running AI agents and LLM apps in production. Its [LLM gateway](https://www.respan.ai/ai-gateway) gives you one OpenAI-compatible API for 1,000+ models across every major provider, and switching models is a one-word change.
OpenRouter
One OpenAI-compatible API for 500+ models from 80+ providers
OpenRouter is an LLM gateway that gives you one OpenAI-compatible API and one key for 500+ models from 80+ providers, including OpenAI, Anthropic, Google, Meta, and Mistral. Stripe [announced an agreement to acquire OpenRouter](https://www.orrick.com/en/News/2026/08/OpenRouter-to-be-Acquired-by-Stripe-to-Help-Businesses-Optimize-Token-Routing-and-Usage) in August 2026.
Portkey
Unified API across major providers
Bifrost
OpenAI-compatible API for 1,000+ models from 20+ providers
Helicone
LLM observability and monitoring
Stainless
SDK generation
Unify
Martian
Intelligent model routing based on prompt type
Kong AI Gateway
AI traffic management
Requesty
400+ model access
Apigee AI Gateway
Google Cloud AI traffic management
The Token Company
Token compression
TrueFoundry
AI Gateway with routing, fallbacks, rate limits, and budgets
OrcaRouter
orcarouter/auto adaptive routing per request
InWorld AI
Conditional routing with CEL expressions on request metadata
Orq.ai
AI gateway for 500+ models with fallbacks, retries, and load balancing
Route every model through one API with automatic fallbacks, spend limits, and caching. Every request is traced and priced in the same place, and evals catch quality regressions before your users do.
Try Respan free