# Capacity classes

> Metered allowance, reserved throughput and dedicated window: what each class promises and when it can be offered.

Source: https://cairva.xyz/docs/capacity-classes

Every lot, request and quote names one capacity class. The class says what's actually being promised, and Cairva only lets a supplier offer a class the route behind it can back.

| Class | Code | What you're buying |
| --- | --- | --- |
| Metered allowance | `METERED_ALLOWANCE` | A prepaid token allowance on a shared route. Rate limits are enforced, but no GPU is dedicated and no tokens-per-second minimum is promised |
| Reserved throughput | `RESERVED_THROUGHPUT` | Provisioned capacity with a measured minimum throughput. Only offered when the supplier has a reserved deployment that Cairva can measure |
| Dedicated window | `DEDICATED_WINDOW` | Exclusive use of a deployment for a fixed time window. Only offered when the hardware is actually set aside for the buyer |

## What every class shares

- A fixed input and output token allowance
- A delivery window
- Requests per minute, tokens per minute and concurrency limits enforced by the gateway
- A hard stop when the allowance is used. There's no overage

## Sandbox routes

Sandbox routes can only offer **metered allowance**. Reserved throughput and dedicated windows need a live route Cairva can measure, so a lot that names either class on a sandbox route is rejected.

> [!NOTE]
> Today the only route is a sandbox route, so the only class you can buy is metered allowance. Reserved and dedicated capacity become possible once a supplier has a live, measurable deployment on Cairva.