Notes / System response time standards


Subset of Guidelines in Miller (1968)

Summary for miller1968:

TopicTiming (sec)
Response to control activation0.1 to 0.2
Response to “System, are you listening?”3
Response to “System, can you do work for me?”2 (simple) 5 (complex)
Response to “System, do you understand me?”2 to 4
Response to identification0.4 to 0.5 (feedback) 0.2 (confirmation)
Response to “Here I am; what work should I do next?”10 to 15
Response to a simple inquiry of listed information2
Response to a simple inquiry of status7 to 10
Response to a complex inquiry in tabular form4
Response to a request for the next page1
Response to “Now, run my problem.”15
Response to the delay following a keyboard entry versus3 (keyboard) 2 (light pen)
a light-pen entry of category for inquiry
Graphic response from light pen0.1
Response to complex inquiry in graphic form2 to 10

Subset of Guidelines in MLT-STD 1472

Summary for mil-std-1472f:

ActionDefinitionTiming (sec)
Key responseKey depression until positive response (e.g., click)0.1
Key printKey depression until the appearance of a character0.2
Page turnEnd of request until the first few lines are visible1.0
Page scanEnd of request until the text begins to scroll0.5
XY entryFrom selection of field until visual verification0.2
FunctionFrom selection of command until response2.0
PointingFrom input of point to display point0.2
SketchingFrom input of point to display of line0.2
Local updateChange to image using local database (e.g., new menu list from display buffer)0.5
Host updateChange where data is at the host in readily accessible form (e.g., scale change of an existing image)2.0
File updateImage update requires an access to a host file10.0
Inquiry (simple)From command until display of a commonly used message2.0
Inquiry (complex)Response message requires seldomly used calculations in graphic form10.0
Error feedbackFrom entry of input until an error message appears2.0

Subset of Guidelines in ESD-TR-86-278

Summary for esd-tr-86-278:

SectionTopic/ActionTiming (sec)Guidance
1.0/4Fast response0.2Maximum time for delays in displayed feedback for normal operation
1.1/5Fast acknowledgment of entry0.2Maximum time to acknowledge the entry of a designated position
1.1/7Responsive cursor control0.5Maximum time for moving the cursor from one position to another
2.7.1/6Fast response to display request0.5 to 1.0System response to a simple request for data display
3.0/28Appropriate computer response time0.5 to 1.0 2.0System response to a control entry System response to simple entries
3.0/19Control availability0.2Maximum time for control delays or lockouts
4.3/11Appropriate response time for error messages2.0 to 4.0Display error message

Subset of Guidelines in TAFIM

Summary for tafim1996:

SectionTopic/ActionTiming (sec)Guidance
6.6.2Work-in-progress window5 secFor simple requests that can be processed under this time, provide simple visual feedback via a brief message. If the request response exceeds this time, the application should provide a window to indicate work in progress.
8.3.1.14Control5 to 200 msSystem response time.
8.3.1.15Feedback15 secIf the user waits more than this time, provide a periodic indication of normal operation.

Response Time by Nielsen

Feedback becomes especially important in case the system has long response times for certain operations. The basic advice regarding response times has been about the same for many years ( miller1968; Card et al. 1991):

  • 0.1 second is about the limit for having the user feel that the system is reacting instantaneously, meaning that no special feedback is necessary except to display the result.
  • 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. Normally, no special feedback is necessary during delays of more than 0.1 but less than 1.0 second, but the user does lose the feeling of operating directly on the data.
  • 10 seconds is about the limit for keeping the user’s attention focused on the dialogue. For longer delays, users will want to perform other tasks while waiting for the computer to finish, so they should be given feedback indicating when the computer expects to be done. Feedback during the delay is especially important if the response time is likely to be highly variable, since users will then not know what to expect.


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