> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ardie.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Pricing & Plans

> Understanding Ardie's prepaid usage model

## Prepaid Usage Model

Ardie uses a **prepaid usage model**. When you purchase access to a knowledge base, you select a plan that includes a fixed number of queries per billing period.

<Info>
  This model ensures transparent pricing with no surprise bills. You always know exactly how many queries you have available.
</Info>

## How Plans Work

Each knowledge base publisher sets their own pricing tiers. A typical knowledge base might offer:

| Plan             | Price    | Queries Included | Best For                 |
| ---------------- | -------- | ---------------- | ------------------------ |
| **Starter**      | \$29/mo  | 100 queries      | Testing and evaluation   |
| **Professional** | \$99/mo  | 500 queries      | Regular usage            |
| **Enterprise**   | \$299/mo | 2,000 queries    | High-volume applications |

## What Counts as a Query?

A **query** is a single API call to the `/kb/{kb_id}/query` endpoint. Each query:

* Counts as 1 against your plan's query limit
* Returns an answer with citations
* Reports `tokens_used` in the response

<Note>
  Failed requests (4xx/5xx errors) do not count against your query limit.
</Note>

## Monitoring Usage

Track your usage in real-time from the [Dashboard](https://ardie.ai/dashboard):

* **Queries Used** — How many queries you've made this period
* **Queries Remaining** — How many queries are left
* **Usage Percentage** — Visual progress toward your cap

## What Happens at the Cap?

When you reach your query limit:

1. API requests return `429 Too Many Requests`
2. The response includes your current usage and cap
3. You can upgrade your plan or wait for the next billing period

```json theme={null}
{
  "error": "query_cap_exceeded",
  "message": "You have exceeded your monthly query cap of 500 queries.",
  "usage": {
    "used": 500,
    "cap": 500
  },
  "upgrade_url": "https://ardie.ai/billing"
}
```

## Upgrading Plans

You can upgrade your plan at any time:

1. Go to your [Dashboard](https://ardie.ai/dashboard)
2. Find the knowledge base subscription
3. Click **Upgrade Plan**
4. Select a higher tier

<Tip>
  Upgrades take effect immediately. Your new query limit is available right away.
</Tip>

## Next Steps

<CardGroup cols={2}>
  <Card title="Purchase Access" icon="credit-card" href="/marketplace/purchasing">
    Learn how to buy access to a knowledge base
  </Card>

  <Card title="Rate Limits" icon="gauge" href="/api-reference/rate-limits">
    Understand rate limiting and caps
  </Card>
</CardGroup>