Fact · Voice and AI
1.0second
Jakob Nielsen's response-time limits say 1.0 second is about the limit for the user's flow of thought to stay uninterrupted, although the user still notices the delay.
Checked against its source on October 17, 2026
In the source's own words
“1.0 second is about the limit for the user's flow of thought to stay uninterrupted, even though the user will notice the delay”
Response Times: The 3 Important Limits, Jakob Nielsen, Nielsen Norman Group, 1993, Section on the 1.0 second limit.
Open the original- What it measures
- The article restates limits from Nielsen's 1993 book Usability Engineering. The limits describe screen interaction; no study in the article tests voice conversation.
- What it does not show
- A usability rule of thumb for interfaces, not a measured threshold for phone calls. Spoken conversation has its own, shorter timing norms.