Math: How Many Steps Equals Good Eyesight?

Reposting this from the BackTo20/20 forum, for our resident darling nerds. :smiley:

Hi Jake,

This is more of a fun mathematical based question instead of a progress report or update. It’s based on CM measurements.

While taking walks I usually like to count how many paces from the point at which I can read a car’s license plate to when I reach the car. My max pace with my last normalize was 50 paces (could be a little more, since it was a casual count, but repeated). It varies though, and a lot of times it’s 40+ paces (I think things like the heat wave coming off the asphalt on the road can interfere). A quick measurement I just did shows I do about 8.5 paces per 20 feet.

When running some numbers, I realized that diopters are very easy to calculate: just 100/your centimeter. You have provided the formula on the website somewhere, but I think it was a bit longer (converting for meters). Anyway, I realized that this is one of those infinite slope things because if you divide 100/2000 you still don’t get 0 (ie. “perfect vision”). So, since 100/800=0.125D I figured that that is a good number to start with to gage for “good natural vision.”

When working out the formula, I got:
800 cm = 26.25′
26.25’*(20’/8.5 paces) = ~62 paces

Hence, “good vision” for me with full prescription would give me 62 paces being the point at which I can read a car’s license plate outside in ideal conditions (sunny, but without squinting, and no heatwave coming off the asphalt).

Again, the max I’ve had with norms is 50 paces.
This translates to less ideal conditions (heat wave interference) of 40+ paces.
New norms (like the ones I just started wearing from yesterday) gives me about 35 (measuring in the less ideal condition mentioned above).

Does all of this seem valid to you? If it is, this means I’d need to be more accurate with my paces (double check pace distance, and counting in various scenarios). Hope it makes sense, though, because for me it might be a fun way of logging data improvement via real world experiences.


You lost me at 50 paces. All that is over my head. I’m 62 and everything had to be simple, give me the calculator. :upside_down_face:

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sounds good except that “paces” are pretty inaccurate. Whose paces? :stuck_out_tongue:


Most folks learn how many paces in say, 50 or 100 meters, then use a pace counter to track distance.

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really? where I’m from hardly anyone uses a pace counter (I do but that’s more to track steps and burnt calories :smiley: )

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There are people and places where fitness trackers aren’t the way. :smile:

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I think it sounds a good idea to count paces. Unless you are going uphill or take to running instead of walking then paces can be a great rough guide to distance (it is used in navigation sports/orienteering all the time). As to how many paces is ‘good eyesight’ I think you can measure against your own numbers to see how you’re going (as you say conditions change, lighting etc. so there might be different ‘norms’ for different conditions). Also where I come from 20.5 meters is the gold standard for reading car number plates, so just work out how many paces it takes you to go 20.5 meters to see if you’ve met that measure of ‘good eyesight’ if you want something more absolute against which to compare your personal pace counts.

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The next generation will know nothing about nothing, unless they’re connected to the Internet. Or so it feels like sometimes, anyway.

Maybe Elon is right and we’re just already half way through the evolution towards being cyborgs. Outsourcing … using the network instead of our brain :stuck_out_tongue: