Being so fast that the eye cannot follow, or the opponent "disappears" from the from your field of vision is a common trope in manga, especially shounen manga. It's usually a high burst of speed over a short distance.
In terms of calcing these sort of feats...
There are three main kinds of faster than the eye to be considered, the third of which is on a order of magnitude higher than the first two. Faster than the movement of the eyes themselves? This will make things appear out of focus and difficult to locate, and is determined by distance in the field of vision in relation to human eye movement speed. Faster than the brain's separation of one event from another? This effect is really the same thing as the first and cannot be focused on and tracked, repeating punches for example appearing as multiple blurs in exactly the same fashion as a helicopter blade. This is determined on this limit of the processing of the brain and the distance the movements occur over. Faster than a human can perceive? This will make a movement imperceptible, and is based on the limits of human time perception, as well as distance of the movement/field of vision. This is the level of speed required for true "teleportation speed" as it is described.
Below 5 milliseconds (a 200th of a second), and peaking towards 1 millisecond (a 1000th) movements are tending towards imperceptibility for humans (This is NOT to be confused with human Reaction Time which the average is around 215 milliseconds, peaking at the physical limit of 100 milliseconds aka 1/10th of a second).
In an experiment, under good circumstances, air force pilots were able to identify an aircraft flashed on the screen for a 220th of a second, but only in a darkened room in which the after-image lingered on the eye. There is a similar phenomena that occurs with sound, and is known as summing localization, in which two sounds are separated by so little time as to appear as the sum of their parts (1 to 5 milliseconds), so it's highly likely that this represents the same range of limitation of the brain. However, it is wise to use the minimum in any calculations rather than the peak.
However, in a fight, good conditions aren't always available, and the feat may not necessarily be depicted as imperceptible to the readers of the manga despite the characters viewpoint. A character witnessing such a feat at close range may not be in the best concentration, which is why caution should be used. Well documented occurrences or attacks/movements that are consistently imperceptible and have multiple witnesses can have the above methodology applied to them. Attacks that are shown as invisible to both character in the fiction and the actual readers could also be considered as candidates for this. Characters using actual leg strength for this feet will have peak kicking speeds > the speed they attained in doing it.
Also to be considered is that while human levels are appropriate as a base minimum for this, reaction times of the characters start to become important when calcing this. For example: A character who dodges a handgun bullet from a 10 centimeters may have reactions of >3402th of a second. This means that they can surely perceive that length of time to react during it. This starts becoming important once their reaction time exceeds human time perception, so this is where reaction times take over for measuring this type of feat.
It should be noted that although this feat can be calced, the absence of this kind of feat does not overwrite distance/time based speed feats which are much more solid. A lot of American comics do not use this method as profusely to portray high speed, as it is a trope-like feat more prevalent to Japan. Faster than the eye moves are often done in a very flashy extravagant way. Given the basis of human perception above, it provides a general rule, however, where it is not consistent with other feats it leads to inflationary values. Therefore, it is better to calc based on the shown reaction times of characters from previous feats (though as mentioned above, this may exceed even the human rate of perception).
Many high tier characters are able to attain these great speeds very generally, however some of the low to mid-tier universes have special speed techniques for achieving this feat.
"Faster than the eye" techniques:
Shakushi - One Piece
Soru - One Piece
Gear 2 - One Piece
Shunpo - Bleach
Sonido - Bleach
Hirenkyaku - Bleach
Shunshin no Jutsu - Naruto
Shundou - Negima
Zanzoken - Dragonball
Keiko - Souten no Ken
Agility - Pokemon
Quick Attack - Pokemon
Shield Roll - Super Smash Bros
Calcs - Speed calculation can be found here (This is an earlier calculation, but it makes the assumption of 0.1 seconds, so take with a pinch of salt. It comes to a conclusion of 89m/s which is more the blurry out of focus kind of "faster than the eye", than actual invisibility.)