An AI gateway is a single API that sits in front of every model provider — OpenAI, Anthropic, Google and the rest — so your app talks to one endpoint with one key instead of integrating each provider separately. It routes the request, meters the cost, and hands back the response in a consistent shape.
Key takeaways
- An AI gateway is one endpoint in front of many model providers.
- It gives you one key, one bill, and a consistent request shape across vendors.
- The real value is in routing, caching, spend caps and fallback — not just proxying.
- You need one once you use more than one model, or care about cost and reliability.
Why not just call providers directly?
Calling one provider directly is fine — until you have two. Then you're holding two SDKs, two API keys, two billing dashboards, two rate-limit regimes, and two slightly different request formats. Add a third model and the glue code to switch between them becomes its own small project. A gateway collapses all of that into one integration.
What an AI gateway actually does
A good gateway is more than a proxy. The features that earn its place:
- One key, one bill. Every provider is reached through a single credential and settled on one prepaid balance — no per-vendor contracts or cards.
- Model routing. You pick a model per request by name; the gateway sends it to the right provider. Switching models is a one-word change.
- Caching & dedup. Identical requests can be served from cache instead of paying for the same completion twice.
- Spend caps. A hard monthly ceiling means a runaway loop can't produce a surprise five-figure bill.
- Fallback. If a provider is down or rate-limited, the request can fail over to a healthy one instead of erroring.
- One response shape. Responses come back in a consistent, OpenAI-compatible format, so your parsing code doesn't branch per vendor.
The model name you pass is the real provider model ID — so the day a provider ships something new, you can call it the moment it's in the catalog. Browse the full model list and live pricing.
How it works in practice
Most gateways are OpenAI-compatible, which means you keep using the OpenAI SDK and change only the base URL and key:
import OpenAI from "openai";
const ai = new OpenAI({
baseURL: "https://withconflux.com/v1",
apiKey: process.env.CFLX_KEY,
});
// Same call, any provider — just change the model name.
const res = await ai.chat.completions.create({
model: "claude-opus-5",
messages: [{ role: "user", content: "Hello" }],
});That one change is the whole migration. From there, swapping claude-opus-5 for gpt-6-astra or a cheaper model is a single string.
Managed vs BYOK
There are two ways to run a gateway, and the difference is whose provider account the call lands on:
| Managed | BYOK (bring your own key) | |
|---|---|---|
| Upstream account | The gateway's | Yours |
| Billing | One prepaid balance, list + flat markup | Provider bills you directly; gateway meters |
| Setup | Nothing to configure | Add your own vendor keys |
| Best for | Shipping fast, one bill | Existing provider contracts / volume deals |
When you need one
You don't need a gateway for a single call to a single model. You start needing one when:
- You use more than one model — or expect to.
- You want to control cost — route cheap work to cheap models and cap spend. (More on that in cutting your AI bill with model routing.)
- You need reliability — fallback when a provider has a bad day.
- You're deciding which provider to build on and don't want to be locked in. (See OpenAI vs Anthropic.)
If you're comparing providers, a gateway lets you test both in production with a one-word change — no second integration to throw away.
Beyond chat models
The same pattern applies to more than text generation. The withConflux gateway also fronts content-AI capabilities — moderation, AI-image detection, music-rights screening and more — on the same key. You can try several of them free in the tools.
An AI gateway turns "integrate every provider" into "integrate once." One key, one bill, every model — see the full lineup and live pricing.