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

# Understanding Call Minutes & Billing

> Learn how Kalimna.ai billing works, including call minutes calculation, phone number rentals, and usage monitoring

Kalimna.ai operates on a **usage-based** model. You pay primarily for two things:

1. The **minutes** your AI spends in calls.
2. Any **dedicated phone number** rentals.

## 1. Included Minutes vs. Pay-as-You-Go

* **Included Minutes**: Some plans may come with a set of monthly minutes. These are consumed first.
* **Pay-as-You-Go**: If you exceed included minutes (or if you're on a usage-based plan), you pay for each additional minute used.

## 2. How We Calculate Minutes

* **Per-Second Billing**: Typically, Kalimna.ai bills by the second (converted to minutes). For example, a 90-second call is 1.5 minutes.
* **Rounding**: Make sure you check your plan's rounding rules. Some might round up to the nearest 30 seconds, while others do pure per-second.

## 3. Monthly Usage & Purchasing Extra

* **Monthly Reset**: If your plan includes minutes, those reset monthly on your billing date.
* **Buying Add-Ons**: You can purchase extra minute bundles if you expect a spike in call volume.

## 4. Additional Costs

* **Phone Number Rental**: A monthly fee for each dedicated inbound/outbound number you rent (varies by region).
* **Possible Carrier Surcharges**: Some countries may have unique taxes or surcharges—check the [Costs & Pricing](../../costs-and-pricing/cost-overview.md) section for more details.

## 5. Monitoring Usage

* **Dashboard**: The platform displays your current usage, how many minutes are left, and your estimated cost so far.
* **Notifications**: You can set up alerts (e.g., "Email me when I hit 80% of monthly minutes") using the no-code automation platform.

**Next Steps**

* Check out our [Costs & Pricing](../../costs-and-pricing/cost-overview.md) section for a deeper breakdown of number rentals, international rates, inbound vs. outbound cost differences, and more.
* Or proceed to [AI Assistants Overview](../../ai-assistants-overview/what-is-an-ai-assistant.md) to build your first agent.