I count difference between small numbers and enums on my fingers.

This includes e.g.

  - the distance between months
  - the distance between wall clocks

It's simpler for me to say "The number of months between March and September is... April, May, June, July, August, September, six." than "The number of months between March, 3, and September, 9, is 9-3 = 6," because I don't cache the numeric value of the months. Maybe I would if I were a Chinese speaker, where September's name is 九月 jiǔ yuè = nine month.

For wall clocks that wrap around midnight, it's simpler to count because it removes dealing with negative numbers.

I count the number of days in a month on my knuckles.

I even sing the 'abcdefg' song to infer letter sort order.

They can be a miniature sort-of-abacus. Keeping track of a number while you're scanning a lot of other things that occupy your mind. You can even sort of hold both the 10¹ digit and the 10⁰ digit on your hands if you're used to it, by semi-extending fingers or other methods, counting up to 100 and "physically" keeping the number in "memory".

Most of the time it's not necessary but if I'm particularly tired I use it sometimes.

I actually learned to count on binary with my fingers at some point. So i can technically count to 32 on one hand and 1024 using both.

It's been useful a handful of times (less than 5 times, not 32).

But it's fun, and not that hard once you learn the pattern.

https://en.wikipedia.org/wiki/Knuckle_mnemonic

What's the highest number you can count on your fingers?

When I need to do something repeatedly for a large number of times, I use my thumb to count the joints of my fingers, where the right hand is the "ones" and the left hand the "tens" column. In practice, I only go up to a hundred (ie. I use the first three fingers on each hand while counting - three on each finger, for 1-9), because decimal. But, the same system could get to 12x12 or 13x13.

A really neat alternative is to count on your fingers using binary. The right thumb is 0, the pointer 2, the middle finger 4, the ring finger 8, etc.

Amazingly, this gets you to over 1000 on your two hands, which is a really neat trick in the right setting. (Casually counting aloud off you fingers is great way to break the ice when you use binary - it is familiar but unexpected, dumb but smart.)

Yes, I do, all the time.

Even more than that, I use my fingers to multiply. When I was in grade school, I had a mental block about memorizing my multiplication tables. I just couldn't do it (and I still don't have most of them memorized, but much more now than then).

My teacher ended up teaching me a finger trick to let me quickly compute any multiplication from 6x6 to 10x10 and I use it to this day. This "one weird trick" was one of the most important things I learned when I was a young lad.

I found this webpage that explains it: http://mathsonline.org/pages/tablesFingers.html

If you were missing any fingers, it might lead to an interesting perspective on imaginary numbers.

I have to count on my fingers to calculate time and dates. Dunno why, but I can’t get it right otherwise

It's a useful communication gesture if the topic of conversation calls for it.

Once you visualise a calculator in your head there's no need to count on fingers. But I've recently learned that there are people incapable of visualizing anything at all, so there's that.

I will commonly count things in safety critical situations with my fingers. Usually accompanied by pointing. And with a second party watching.

A very common technique used in Hindu/Buddhist Japa Meditation is to count the phalanges/creases in each finger including the tip thus making 4x5=20 count in one hand. For each 20 count of the right hand use 1 phalange/crease of the left hand and thus you can easily count upto 20x20=400 in a single complete cycle.

Occasionally for routine small counting.

What I did find interesting is that I've used it more for Japanese especially when I'm in Japan. I've been very slowly learning Japanese and of course counting in Japanese. So if I'm ordering food someplace I try to either count (yen) change or figure out the amount of an item I'm ordering.

I remember when I moved to the U.K. and asked at my new workplace for some memory sticks. - How many do you need? - Two. And I raised two fingers accordingly. - Here, in the UK, you don't do that with your fingers.

That day I learnt something new about cultural differences.

I get embarrassed counting on my fingers during exams. I can't seem to kick this habit.

IIRC some cultures use a nifty method where the right hand is the ones column, the left hand is the tens column, and the thumb indicates five (sort of like an abacus).

Then each hand can represent 0 to 9, and together they go to 99.

Yes, counting rests (sections where I'm not playing) when playing in the band. That way, my fingers keep going even if I'm distracted by other things.

I suppose you could say I'm counting time, rather than things.

anybody remember this being pushed, K-TEL record style?

https://en.wikipedia.org/wiki/Chisenbop [circa.US 1977]

No, I count with my toes on both sides: 1 is all left toes and 2 is all right toes, 3 left again and so on. With a small break after each even number. I guess one could call it a tic.

I’ve noticed I count syllables on my fingers when writing in meter.

Sumerians counted to 12 on one-hand.

https://en.m.wikipedia.org/wiki/Sexagesimal

The sexagesimal system used by the ancient babylonians and sumerians is believed to involve counting using the finger bones of our hand

I often count by a rhythm feel for smaller numbers. Maybe subdivide into rhythms of four and then count each of them manually.

When I want to count two things at the same time, sometimes I will count one of them by hand.

I count rests in orchestra by counting in finger binary, 31 on one hand is enough for a cello.

I still count days in months using my fingers. :)

Yes, in binary. Addition and multiplication.

Yes. And, I count in binary to stop myself speaking in bullshit meetings.

chunking