OpenRouter Alternative for Budget-Controlled AI API Usage

Not a full replacement — a focused gateway for small teams that need virtual keys, budgets, and usage tracking without self-hosting.

CostLLM is not trying to replace every model marketplace.

OpenRouter is great for model discovery and multi-provider routing. CostLLM focuses on a narrower problem: helping small AI products control usage and cost before the provider bill grows out of control.

If your product uses one shared provider API key, it becomes difficult to answer basic questions:

• Which user is burning credits?
• Which project is driving the bill?
• Can I set a hard budget per key?
• Can I stop abuse before the provider bill grows?

CostLLM solves this with an OpenAI-compatible gateway, virtual API keys, usage tracking, hard budget limits, rate limits, and simple billing visibility.

Core Features

• Virtual API keys — Create separate keys for each user, project, or environment.
• Usage tracking — Monitor token usage per key in real time.
• Budget limits — Set hard spending caps per key. Usage stops when the budget is reached.
• Rate limits — Prevent abuse and retry loop spikes.
• Simple billing — Clear dashboard for API keys, usage, and credits.
• OpenAI-compatible — Use the standard /v1/chat/completions endpoint.
• No prompt content logging — CostLLM only stores token counts and metadata needed for billing, limits, and abuse prevention.

Who Is This For?

• AI wrapper builders — Know your per-user margin before scaling.
• Small SaaS teams — Prevent one user from blowing the entire API budget.
• Bot and agent developers — Cap spending on autonomous workflows.
• Indie hackers — Launch with cost controls from day one.
• Teams worried about LLM API costs — Stop bill shock before it happens.

Quick Start — One Line Change

Your app keeps using the OpenAI-compatible endpoint. Just swap the base URL and API key:

curl https://api.costllm.ai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_COSTLLM_KEY" \
  -d '{
    "model": "deepseek-v4-flash",
    "messages": [
      {
        "role": "user",
        "content": "Write a short onboarding email for a SaaS user."
      }
    ]
  }'

CostLLM vs OpenRouter