What are LLM Gateways?
LLM gateways are proxy servers that sit between your application and LLM providers. They provide a unified API, automatic failover, load balancing, caching, cost tracking, and access to 100+ models through one endpoint. Essential for production AI applications that need reliability and cost control.
Answer-Ready: LLM gateways proxy AI requests through a unified API. Top tools: LiteLLM (open-source, 200+ models), Bifrost (fastest, sub-100us), Portkey (enterprise), OpenRouter (pay-per-use marketplace). Provide failover, caching, cost tracking, and multi-provider routing.
Best for: Teams running AI in production needing reliability and cost control. Works with: Any LLM provider and AI coding tool.
Gateway Comparison
Feature Matrix
| Feature | LiteLLM | Bifrost | Portkey | OpenRouter |
|---|---|---|---|---|
| Type | Open-source | Open-source | Enterprise | Marketplace |
| Models | 200+ | 1000+ | 250+ | 300+ |
| Overhead | ~1ms | <100us | ~2ms | ~50ms |
| Failover | Yes | Yes | Yes | Yes |
| Caching | Yes | Semantic | Yes | No |
| Cost tracking | Yes | Yes | Yes | Built-in |
| Load balancing | Yes | Yes | Yes | Automatic |
| Self-hosted | Yes | Yes | Yes | No |
| Free tier | Unlimited (OSS) | Unlimited (OSS) | 10K req/mo | Pay-per-use |
When to Use Each
| Gateway | Best For |
|---|---|
| LiteLLM | Teams wanting open-source flexibility with most provider support |
| Bifrost | High-throughput apps needing minimal latency overhead |
| Portkey | Enterprise teams needing compliance, guardrails, and analytics |
| OpenRouter | Indie developers wanting simple pay-per-use access to all models |
Setup Examples
LiteLLM — Universal Proxy
from litellm import completion
# Same API for any provider
response = completion(
model="anthropic/claude-sonnet-4-20250514",
messages=[{"role": "user", "content": "Hello"}],
)
# Switch to: openai/gpt-4o, gemini/gemini-2.5-pro, etc.Bifrost — Claude Code Integration
npx -y @maximhq/bifrost
claude mcp add --transport http bifrost http://localhost:8080/mcpPortkey — With Guardrails
from portkey_ai import Portkey
client = Portkey(api_key="...", config={
"retry": {"attempts": 3},
"cache": {"mode": "semantic"},
"guardrails": ["pii-filter", "toxicity-check"],
})OpenRouter — Simple Access
from openai import OpenAI
client = OpenAI(
base_url="https://openrouter.ai/api/v1",
api_key="sk-or-...",
)
response = client.chat.completions.create(
model="anthropic/claude-sonnet-4-20250514",
messages=[{"role": "user", "content": "Hello"}],
)Cost Optimization Strategies
| Strategy | How |
|---|---|
| Model routing | Simple tasks → cheap model, complex → premium |
| Caching | Cache identical/similar requests |
| Fallback chain | Primary fails → cheaper backup |
| Budget limits | Hard caps per project/user |
| Token tracking | Monitor and optimize token usage |
FAQ
Q: Do I need a gateway? A: For production, yes. For prototyping, direct API calls are fine. Gateways add reliability, cost control, and flexibility.
Q: Can I use a gateway with Claude Code? A: Yes, LiteLLM and Bifrost both support Claude Code integration via MCP or API proxy.
Q: Which is cheapest? A: LiteLLM and Bifrost are free (open-source, self-hosted). OpenRouter charges a small markup on model pricing.