ChatGPT Core Web Vitals
How real Chrome users experience chatgpt.com, from Google's Chrome UX Report: the 75th percentile of visits on every device.
ChatGPT fails Core Web Vitals
Sep 27 – Oct 24, all devices
INP
669 ms
Poor
LCP
4.2 s
Poor
CLS
0.17
Needs improvement
FCP
2.3 s
Needs improvement
TTFB
1.2 s
Needs improvement
INP over time
Weekly p75. The dashed line is the 200 ms "good" threshold.
What the numbers say
- ChatGPT fails Core Web Vitals on Largest Contentful Paint (4.2 s, good is 2.5 s or less) and Cumulative Layout Shift (0.17, good is 0.10 or less) and Interaction to Next Paint (669 ms, good is 200 ms or less).
- Time to first byte is 1.2 s, so most of the LCP time is spent after the first byte: loading the main image, fonts or scripts.
- Among 10 ai sites we track, ChatGPT has the 9th fastest LCP.
- INP has worsened by 42 ms over the last 25 weeks, from 627 ms to 669 ms.
Keep a site like this from getting slower
Real-user data shows a regression weeks after it ships. Vitalgate runs Lighthouse on every pull request and fails the check when a change breaks budgets like these: LCP ≤ 4.2 s, CLS ≤ 0.17, FCP ≤ 2.4 s.
Other ai sites
| Site | Core Web Vitals | LCP | INP | CLS |
|---|---|---|---|---|
| OpenAI | Fails | 2.9 s | 219 ms | 0.00 |
| Anthropic | Passes | 1.4 s | 67 ms | 0.00 |
| Claude | Fails | 2.7 s | 157 ms | 0.01 |
| Hugging Face | Passes | 1.1 s | 51 ms | 0.00 |
| Perplexity | Fails | 4.6 s | 353 ms | 0.03 |
| Midjourney | Fails | 2.7 s | 223 ms | 0.00 |
| Mistral AI | Fails | 2.9 s | 101 ms | 0.08 |
| Replicate | Passes | 2.4 s | 73 ms | 0.08 |
| Groq | Passes | 1.1 s | 95 ms | 0.00 |