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

# Limits

<Tip>
  This page is about the **Limits** view in your application's settings. It is
  not about reducing your billable request count. For that, see [Limiting
  requests](/support/limiting-requests).
</Tip>

The **Limits** page shows the top-10 custom metrics in your app by unique key
count from the last recorded minute. Above the table, it also shows your app's
total unique keys and the recorded time for that minute.

A unique key is one custom metric name plus one combination of tag values.

## What the page shows

For each of the top 10 custom metrics, the page lists:

* **Metric name:** the name of the custom metric.
* **Unique keys:** how many distinct tag combinations were seen in the last
  recorded minute, and the share of your app's total.
* **Tag examples:** a sample of the tag combinations being reported. Use this
  column to spot tags with many different values. If there are more examples,
  the page shows a `+ more` link.

## When to use this page

If you're seeing gaps in your custom dashboards, use this page to check whether
any metric is generating many unique keys. High-cardinality tags are a common cause.

To reduce the number of unique keys, review the tags on that metric and use a
limited range of tag values when possible.

## See also

* [Custom metrics](/metrics/custom)
* [Metric tags](/metrics/custom#metric-tags)