Skip to main content

TTFB by data save mode

TTFB by data save mode without noise

Vasil Dachev avatar
Written by Vasil Dachev
Updated over 2 weeks ago


What is TTFB by data save mode

TTFB by data save mode shows Time to First Byte (TTFB) egmented by whether users have enabled their browser or device’s Data Save mode.

This lens helps uncover whether users trying to reduce their data usage face slower server responses — often tied to routing, caching, or protocol decisions.


Healthy TTFB by data save mode sample


Should you worry

In a healthy setup:

  • TTFB is fast and consistent regardless of Data Saver setting

  • Data Saver users may even benefit from smaller initial payloads or CDN optimizations

  • The backend efficiently supports all network types without discrimination

This indicates a server architecture that adapts well and delivers reliably across varying user preferences.

Unhealthy TTFB by data save mode sample

If Data Saver users experience noticeably slower TTFB, common culprits include:

  • Unoptimized server logic for lighter or fallback versions of your site

  • Caching headers not applying uniformly to Data Saver requests

  • Misconfigured redirects, especially for mobile or proxy-based requests

  • CDN edge misbehavior for alternate UA strings or reduced headers

This can severely affect perceived performance — especially for first-time visitors or those on poor connections.

Resolving unhealthy TTFB by data save mode

Go-to action plan to resolve an unhealthy TTFB by data save mode:

  1. Ask Uxi to analyze your TTFB by data save mode values and suggest improvements.

  2. Use Filters to zoom in on slow TTFB pages with Data Save mode enabled and spot hidden patterns.

  3. Simulate TTFB of the suspected lens to see if fixing it will resolve the TTFB by data save mode. If yes, this is where the resolution focus should be.

  4. Use an automated optimization tool like Navigation AI to improve your TTFB by data save mode values.

  5. Once you’ve improved TTFB, set an alert to be the first to know if it starts worsening again.

Try it yourself

Discover how your website performs with real user data.

Did this answer your question?