Last updated 2026-05-13. Pricing, model names, and provider policies change frequently.
Quick answer
An LLM API aggregator gives you access to multiple models or providers through one interface. Aggregators are useful for experimentation, fallback, and routing, but they also add a dependency between your app and upstream model providers.
What aggregators provide
Common features include unified API access, model catalogs, fallback, routing, usage tracking, key management, and sometimes observability or caching. The value is operational convenience across providers.
The dependency tradeoff
An aggregator can simplify integration, but outages, policy changes, pricing changes, or routing behavior can affect your app. Production teams should know how to bypass or replace the aggregator if needed.
When aggregators are a good fit
They are especially useful for model comparison, early experimentation, fallback strategies, and teams that want one interface while evaluating several providers.
Provider examples to compare
| Provider | Category | Supported models | OpenAI-compatible | Starting price | Context | Tool calling | Vision | Streaming | Status | Trust | Links |
|---|---|---|---|---|---|---|---|---|---|---|---|
| OpenRouter | LLM API Aggregators | GPT, Claude, Gemini, DeepSeek-V4 | Yes | Varies by model route | Model dependent across upstream routes | No | Yes | Yes | Available | 11/15 | |
| Portkey | LLM API Aggregators | GPT, Claude, Gemini, DeepSeek-V4 | Yes | Plan dependent plus provider spend | Provider dependent | No | Yes | Yes | Available | 11/15 | |
| LiteLLM Cloud | LLM API Aggregators | GPT, Claude, Gemini, Mistral | Yes | Plan dependent | Provider dependent | No | Yes | Yes | Unclear | 10/15 | |
| Helicone | LLM API Aggregators | provider dependent | Yes | Plan dependent | Provider dependent | No | Yes | Yes | Available | 11/15 | |
| OpenAI | Official APIs | GPT, reasoning models, embeddings, image | Yes | Budget to premium GPT tiers | Short to very long, model based | Yes | Yes | Yes | Available | 12/15 | |
| Anthropic | Official APIs | Claude, Claude Haiku, Claude Sonnet, Claude Opus | No | Mid to premium Claude tiers | Long context options | Yes | Yes | Yes | Available | 10/15 |
Checklist
- Understand whether traffic is routed, proxied, logged, or transformed.
- Check upstream provider disclosure and data handling claims.
- Compare total cost against direct provider access.
- Decide what happens if the aggregator is unavailable.
Recommended next step
Compare aggregator options and decide whether you need routing, observability, or simply direct model access.
FAQ
Is an aggregator the same as a gateway?
The terms overlap. Aggregators emphasize model access; gateways often emphasize routing, policy, observability, and controls.
Do aggregators improve reliability?
They can if fallback is configured well, but they can also become another point of failure.
Should enterprises use aggregators?
Sometimes, but legal, security, logging, and data processing requirements need careful review.