---
title: "Web Vitals"
description: "Learn more about Web Vitals issues and how to diagnose and fix them."
url: https://docs.sentry.io/product/issues/issue-details/performance-issues/web-vitals/
---

# Web Vitals

Web Vitals issues are created for the highest opportunity pages in a project when their vitals scores fall into the [`Meh`](https://docs.sentry.io/product/insights/frontend/web-vitals.md#performance-score) or [`Poor`](https://docs.sentry.io/product/insights/frontend/web-vitals.md#performance-score) threshold for an extended period of time.

## [Detection Criteria](https://docs.sentry.io/product/issues/issue-details/performance-issues/web-vitals.md#detection-criteria)

This issue is currently only available for browser SDKs.

The detector for this performance issue runs on a schedule and checks the 7 day average Web Vitals scores for the top 5 [highest opportunity](https://docs.sentry.io/product/insights/frontend/web-vitals.md#opportunity) pages on your website (*the pages that are both high traffic, and have issues worth fixing*).

The following additional criteria must hold true:

* You must have [Seer](https://docs.sentry.io/product/ai-in-sentry/seer.md) enabled on your Sentry account.
* You must have a [GitHub code mapping](https://docs.sentry.io/organization/integrations/source-code-mgmt/github.md) configured for your project.
* There must be at least `10` sample spans for the given vital (*this value is [configurable](https://docs.sentry.io/product/issues/issue-details/performance-issues.md#configuration)*).
* There must be no issues currently open for the same Web Vitals metrics on the page being evaluated.

## [Span Evidence](https://docs.sentry.io/product/issues/issue-details/performance-issues/web-vitals.md#span-evidence)

You can view the [Web Vitals Insights](https://docs.sentry.io/product/insights/frontend/web-vitals.md) dashboard to get an understanding of what pages will trigger the Web Vitals performance issue:

* A *loading / render performance issue* will be opened, if [Time to First Byte](https://web.dev/articles/ttfb#what_is_ttfb) (TTFB), [Largest Contentful Paint](https://web.dev/articles/lcp#what-is-lcp) (LCP), or [First Contentful Paint](https://web.dev/articles/fcp#what-is-fcp) (FCP) falls into or below the `Meh` threshold.
* A *page stability issue* will be opened, if [Cumulative Layout Shift](https://web.dev/articles/cls#what-is-cls) (CLS) falls below the `Meh` threshold.
* An *interaction performance issue* will be opened, if [Interaction to Next Paint](https://web.dev/articles/inp#what-is-inp) (INP) falls below the `Meh` threshold.

## [How to Fix Web Vitals Issues](https://docs.sentry.io/product/issues/issue-details/performance-issues/web-vitals.md#how-to-fix-web-vitals-issues)

We highly recommend using [Seer's Autofix](https://docs.sentry.io/product/ai-in-sentry/seer.md#autofix) functionality to diagnose and fix the Web Vitals Issues we've opened. Alternatively, there is lots of great documentation online about how to improve specific web vitals metrics, see:

* [Optimize Largest Contentful Paint](https://web.dev/articles/optimize-lcp).
* [Optimize Cumulative Layout Shift](https://web.dev/articles/optimize-cls).
* [Optimize Interaction to Next Paint](https://web.dev/articles/optimize-inp).