# NCU Limits and Capacities

## CU capacity

Track your CU usage at a glance with the leftmost tile in the **OVERVIEW** context tab of your resource monitoring dashboard:

## CU limits

CU limits help you control costs by setting usage boundaries for application runs with ["Included" size](https://docs.nuvolos.com/features/applications/application-resources#size-and-price-of-an-application) configurations. Every Nuvolos subscription comes with a total CU limit that you can distribute across your resource pools.

**Why set CU limits?** They're an effective tool for managing resource pool or project costs.

**What defines a CU limit:**

* **CU Limit (Capacity)**: The total CU hours allocated for your subscription period. Each "Included" size application run [mapped to this resource pool](https://docs.nuvolos.com/pricing-and-billing/resource-pools-and-budgets#mapping-a-space-during-space-lifetime) draws from this capacity. For example, a 2 CU application running for 3 hours consumes 6 CU hours.
* **CU Limit Term Start**: When your limit becomes active (your contract start or renewal date)
* **CU Limit Term End**: When your allocated hours expire (your subscription period end date)

### Tracking your consumption

The CU Capacity tile displays total usage across all [application sessions](https://docs.nuvolos.com/features/applications/sessions) configured with "Included" sizes during the active subscription period. The progress bar provides a quick snapshot of consumption since your CU limit started.

**Want to dig deeper?** Resource pool managers can click the **DETAILS** button at the bottom right corner of the tile to see how usage accumulated over time. This opens the **PLAN UTILIZATION** content tab with the date range preset to match your current CU limit subscription period.

### What happens when you reach your limit

Once you reach your limit or your CU limit expires, "Included" size applications can still:

* Start normally,
* Continue running without interruption.

Everything continues to function as long as you maintain a positive credit balance.

**Your options when you exceed your CU capacity:**

1. **Purchase more CU capacity**: Contact your Account Manager to add CU hours to your subscription
2. **Use credits**: Pay for excess CU hours with credits. Note that a positive credit balance is required to start new "Included" size applications during overage. Check the [prices page](https://app.nuvolos.cloud/service-prices) for current overage rates.

{% hint style="info" %}
**Quick summary:**

* CU hour consumption applies **only to "Included" size configurations**
* Consumption depends on your session configuration:
  * Application size (e.g., 4 CU, 16 CU)
  * Add-ons (e.g., Redis, PostgreSQL)
* Once you exhaust your CU capacity, credit charges begin automatically
  {% endhint %}

Track credit deductions from CU overage on the [Credit Utilization](https://docs.nuvolos.com/administration/monitoring-resource-usage/..#credit-utilization-view) content tab.

### Resource pools without CU limits

Some resource pools don't have CU limits configured. In these cases, only credit-based size applications can run.