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

# Billing & quota

> How your balance is charged, what you pay for, and how to cap per-token spend

FortAPI is **pay-as-you-go**: your account holds a balance in USD, and each successful call deducts from it based on usage.

## How charging works

The cost of a request ≈ **usage × that model's price**:

* **Input tokens + output tokens**: most chat / text models are billed on input and output token counts, and input vs. output usually have **different prices**.
* **Cache hits**: the portion served from prompt cache is usually priced **lower**.
* **Images / audio**: image generation, transcription, TTS, etc. may be billed per image, per second, or on a dedicated token basis.
* **Some models are per-call**: a few models have a fixed price per call rather than per-token pricing.

**Per-model prices are defined on the main site's Pricing page.** The console **Logs** page shows exactly how much each request cost.

<Note>
  Balance and **rate limits** are different things: balance governs "how much total you can spend," rate limits govern "how many requests per unit time" (see [Rate limits](/en/rate-limits)).
</Note>

## Capping spend per token

When you create a token you can set a **spend limit** that caps how much **that one** key can spend. Useful for:

* Giving a project / script its own budget that stops when exhausted, without affecting other keys on the account;
* Bounding the blast radius of a key that might leak.

See [Authentication & API keys](/en/authentication) for details.

## Topping up & checking balance

* Your current balance is shown on the console home page.
* Historical usage and per-request detail live under **Logs**.
* When the balance runs out, requests return `403` (see [Errors](/en/errors)); top up to resume.