---
title: Analytics
description: Measure and track page performance using Next.js Speed Insights
url: "https://nextjs.org/docs/13/app/building-your-application/optimizing/analytics"
docs_index: /docs/13/llms.txt
lastUpdated: 2023-09-13
prerequisites:
  - "Building Your Application: /docs/13/app/building-your-application"
  - "Optimizing: /docs/13/app/building-your-application/optimizing"
---

> For an index of all documentation, see [/docs/13/llms.txt](/docs/13/llms.txt).

[Next.js Speed Insights](https://nextjs.org/analytics) allows you to analyze and measure the performance of
pages using different metrics.

You can start collecting your [Real Experience Score](https://vercel.com/docs/concepts/speed-insights#core-web-vitals-explained?utm_source=next-site\&utm_medium=docs\&utm_campaign=next-website) with zero-configuration on [Vercel deployments](https://vercel.com/docs/concepts/speed-insights?utm_source=next-site\&utm_medium=docs\&utm_campaign=next-website).

The rest of this documentation describes the built-in relayer Next.js Speed Insights uses.

## Web Vitals

[Web Vitals](https://web.dev/vitals/) are a set of useful metrics that aim to capture the user
experience of a web page. The following web vitals are all included:

- [Time to First Byte](https://developer.mozilla.org/docs/Glossary/Time_to_first_byte) (TTFB)
- [First Contentful Paint](https://developer.mozilla.org/docs/Glossary/First_contentful_paint) (FCP)
- [Largest Contentful Paint](https://web.dev/lcp/) (LCP)
- [First Input Delay](https://web.dev/fid/) (FID)
- [Cumulative Layout Shift](https://web.dev/cls/) (CLS)
- [Interaction to Next Paint](https://web.dev/inp/) (INP) *(experimental)*

---

For a semantic overview of all documentation, see [/sitemap.md](/sitemap.md)

For an index of all available documentation, see [/docs/13/llms.txt](/docs/13/llms.txt)