Message Fade Timing

Question

Sometimes one wishes to display a message for some time before removing it in some way (in my case fading). When implementing this idea, a problem arises: how long should the message remain fully visible on the screen before fading (fading is fast)?

I am certain that the time should be in some way related to the length of the message (you can read a "Hello World" message in 5 seconds but not the first paragraph of a book). Perhaps an initial delay should also be added.

I have constructed a formula that works so far (see below), but I would like additional advice or better yet, experimental results (if any are available).

My current forumula (result is in milliseconds):

500 + 100 * length

Answer 1

Chris, by all means write a formula if this works, but don’t forget to test it out on users too. There are other factors that you will also need to consider:

• The readability of the font chosen
• The size of the text
• The colour and contrast of the text
• How much other UI surrounds the message (noise)

Testing with users on whether they are able to capture all of the information before the next message fades will be vital to your success.

Furthermore, consider the importance level of the message. Is it crucial for the user to see the message, or is it okay for them to miss it? If the message is crucial, you will need to think about displaying an alert or a flag somewhere within the interface so that the message may be retrieved.

Another consideration that you could use: Is there a max character limit for the message? For instance, I use Tweetdeck and a tweet is no more than 140 characters long. Each of the messages that appear when I am not focused on the app display for the same length of time, comfortable to read 140 characters.