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

# Pricing

> Plans are metered on two units: probes and challenges.

Heretic meters two things. A **probe** is one measured browser session: the collector ran, the sensor took its readings, a verdict exists. A **challenge** is one verification ceremony minted, whether by the widget or by the API. Identity output is part of every probe, not a separate tier.

| Plan       | Monthly    | Probes    | Challenges |
| ---------- | ---------- | --------- | ---------- |
| Sandbox    | Free       | 1,000     | 100        |
| Signal     | \$250      | 10,000    | 1,000      |
| Anomaly    | \$750      | 25,000    | 2,500      |
| Incursion  | \$3,500    | 100,000   | 10,000     |
| Scale      | \$12,500   | 1,000,000 | 100,000    |
| Enterprise | Contact us | Unmetered | Unmetered  |

Overage on a paid plan is **$0.0025 per probe** and **$0.025 per challenge**.

## What happens at the limit

* **Sandbox stops.** It is for building. At the limit the sensor opens no more sessions for your sites until the month turns, the API answers `402` to a mint, and the widget reports `quota-exceeded`.
* **Paid plans keep serving.** The excess is billed as overage.
* **Enterprise is unmetered.**

Read this month's counts at any time with [`GET /v1/usage`](/api/challenge-endpoint#usage) or on the dashboard's **Plan & usage** page, which is also where you choose a plan, change card, see invoices, and cancel.

## Why these numbers

A challenge is priced against what it replaces: an SMS one-time code. A probe is priced per visitor, discounted for the fact that Heretic is not your front door. It sits behind your own funnel, on the pages you choose, so it does not see every visitor and is not priced like a CDN.


## Related topics

- [Dashboard, sites, and keys](/dashboard/dashboard-and-keys.md)
- [Challenge and usage endpoints](/api/challenge-endpoint.md)