What Is an AI API Gateway?
Most teams start with a single API key from OpenAI. Then they add Anthropic. Then a specialized model for code. Then another for reasoning. Within months they have keys scattered across 12 files, no visibility into what anything costs, and no way to swap a model without rewriting half the codebase.
An AI API gateway solves this. It sits between your application and your AI providers, gives you one unified API endpoint, and adds a layer of observability, routing, and control on top. You send one request to the gateway, it forwards to the right model, logs the interaction, and hands back the response. The model providers never know the difference.
In 2026, three tools dominate this space: Helicone, LiteLLM, and Portkey. They serve different audiences and come with very different price tags. This guide breaks down what each one actually does, what it costs, and which one belongs in your stack.
Helicone: The Developer-First Observability Platform
Helicone started as a logging layer for LLM calls. You point it at your OpenAI API key, and it logs every request, response, token count, latency, and cost without changing your code. Since then it has grown into a full AI gateway with caching, prompt management, and model routing.
The biggest selling point is simplicity. If you just want to understand what your AI calls are doing, Helicone gets you there in minutes. Add one header to your API calls, create a free account, and you are in. No infrastructure to manage.
Pricing
- Hobby (Free): 10,000 requests per month, 1GB storage, 1 seat, 1 organization
- Pro ($79/month): Unlimited seats, alerts and reports, HQL query language, usage-based pricing on top
- Team ($799/month): 5 organizations, SOC-2 and HIPAA compliance, dedicated Slack channel, usage-based pricing on top
- Enterprise: Custom MSA, SAML SSO, on-prem deployment, bulk cloud discounts. Contact sales.
The free tier is genuinely useful for solo developers and small projects. Pro and Team add costs on top of the flat fee based on usage, so budget accordingly before you commit.
Where Helicone Falls Short
Helicone is not a full routing engine. Its model routing capabilities are real but limited compared to LiteLLM. If you need sophisticated fallbacks, load balancing across multiple deployments, or fine-grained cost controls per model, you will hit walls. It also does not support as many providers natively as LiteLLM.
LiteLLM: The Open-Source Powerhouse
LiteLLM is the tool that platform teams reach for when they need serious control. It is open source, self-hosted, and completely free to run on your own infrastructure. You deploy it behind your API, configure a YAML file with your provider keys, and get a single OpenAI-compatible endpoint that routes to 100+ models across every major provider.
Where Helicone is a logging platform that grew into a gateway, LiteLLM is a gateway first that added logging. The architecture reflects this: it is built for teams that want to own their infrastructure, control costs through model routing, and avoid paying a SaaS tax on every API call.
Pricing
- Open Source (Free): Self-hosted, no per-token fees, no seat limits. Run it on any cloud or on-prem.
- Enterprise: Starts around $250/month, adds governance, security, and support features on top of the open-source core.
There is no pricing trap here. The core product is free and will remain free. Enterprise adds the stuff that matters at scale: SLAs, compliance features, and support.
What LiteLLM Actually Gives You
With LiteLLM you get spend tracking per model and user, virtual keys to share with teams without exposing real credentials, automatic retries and fallbacks, rate limiting, and load balancing across multiple deployments of the same model. If model A fails, it routes to model B automatically. If one provider is rate-limited, it shifts load elsewhere without your code knowing.
The catch is that you have to run it. That means Docker, a server, maintenance, and the operational overhead that comes with self-hosting anything. If your team does not have the chops to manage that, LiteLLM becomes a liability rather than an asset.
Portkey: The Enterprise Observability and Routing Platform
Portkey positions itself as a full AI gateway for production teams. It offers observability, prompt management, model routing, and guardrails in a single managed platform. In late 2025 it rebranded its enterprise tier as PRISMA AIRS, which tells you something about where the product is heading: bigger, faster, more enterprise.
Portkey is the most opinionated of the three about what a production AI stack should look like. It comes with a built-in model catalog that tracks real-time pricing for 3,700+ models, letting you make routing decisions based on actual cost rather than guesswork. It also has guardrails, which let you filter outputs and block prompts that do not meet policy.
Pricing
Portkey offers a free tier that covers prototyping and evaluation. Paid plans are usage-based and scale with your call volume. Exact pricing is not publicly listed, which means enterprise deals are negotiated. If you are running serious production traffic, expect to pay more than Helicone Pro for comparable volume.
The free tier is a legitimate option for small projects and evaluation. But once you are routing production traffic, the cost climbs. Teams running millions of calls per month have reported meaningful bills.
Portkey Tradeoffs
The managed nature of Portkey is both its strength and its weakness. You get a polished UI, no infrastructure to manage, and enterprise features out of the box. But you also pay a premium for that convenience, and you are dependent on their platform availability. For startups and smaller teams, the cost can be hard to justify when free and self-hosted alternatives exist.
Head-to-Head: Helicone vs LiteLLM vs Portkey
| Feature | Helicone | LiteLLM | Portkey |
|---|---|---|---|
| Cost to start | Free (10K/mo) | Free (self-hosted) | Free (prototyping) |
| Provider support | 60+ | 100+ | 150+ |
| Self-hosted option | Yes (Enterprise) | Yes (core product) | No (managed only) |
| Model routing / fallbacks | Basic | Advanced | Advanced |
| Cost tracking | Yes | Yes | Yes |
| Guardrails | No | No | Yes |
| Compliance features | SOC-2/HIPAA (Team+) | Enterprise only | Enterprise |
| Best for | Observability-first teams | Platform teams owning infra | Enterprises needing governance |
Which Should You Pick?
These three tools serve different teams. The right choice depends on where you are in the AI maturity curve.
Pick Helicone if you want to understand what your AI calls are doing without changing your architecture. The free tier is generous, setup takes 10 minutes, and the logging UI is genuinely good. The limits hit fast if you need real routing or compliance features.
Pick LiteLLM if you have the engineering capacity to self-host and you need serious routing control. If you are running a platform that serves multiple internal teams, or if you need to balance costs across providers intelligently, LiteLLM is built for that. The price is right at zero.
Pick Portkey if you are an enterprise team that needs guardrails, compliance, and a managed platform with SLA guarantees. If you are paying for observability and governance rather than just tooling, Portkey earns its keep.
Many teams end up using more than one. A common pattern: LiteLLM for routing and cost control in production, Helicone on top for the observability layer that LiteLLM’s logging does not quite match. Portkey tends to stand alone because its enterprise features do not pair naturally with the other two.
What This Actually Costs at Scale
Here is the honest math on three common scenarios.
Solo developer or small team, under 500K API calls per month: Helicone Hobby is free. LiteLLM is free. Portkey free tier covers you. You pay only your actual model costs, nothing to the gateway. This is the easiest buying decision you will make all year.
Growing startup, 1-5M calls per month: Helicone Pro at $79 plus usage-based costs runs you roughly $150-$300/month total. LiteLLM stays free if you self-host, but you are paying engineering time to maintain it. Portkey at this volume starts entering serious money with negotiated enterprise pricing.
Scale team, 10M+ calls per month: Helicone Team at $799 plus usage-based fees could run $1,500-$3,000/month depending on your storage and request volume. LiteLLM Enterprise around $250/month plus infra costs. Portkey enterprise pricing is negotiated and varies widely. At this scale, the cost of the gateway is small relative to the value of the routing and cost controls, so choose based on what reduces your model bill, not just the platform fee.
Bottom Line
AI API gateways are not optional anymore. Once you are running more than one model or more than a few thousand calls a month, the visibility and control a gateway provides pays for itself in reduced waste and faster debugging. The three options here cover the full spectrum from free-and-simple to enterprise-managed.
If you want the shortest path to understanding your AI spend: start with Helicone. If you want full control and have the infrastructure capacity: deploy LiteLLM. If you are in an enterprise environment with compliance requirements: talk to Portkey.
The worst choice is doing nothing. Scattered API keys and zero observability is the expensive option.