Which numbers are good to memorize?

After a few months of work I’ve created a PAO system for memorizing numbers, but now my problem is I can’t think of many numbers to memorize. I’ve memorized my credit card numbers, my driver’s license, my new phone number, and the number of miles on my car, but I’m running out of ideas of useful numbers to memorize. Any suggestions? Obviously I could memorize random numbers like pi, but I’m looking for numbers that are more useful in daily life. Thanks.


You could memorize the number for the braille cells A-Z… not too much of an effort and you’ll have learnt the basics of reading braille.


You mention pretty much the most basic numbers one should know. But what about the phone numbers you use more than others? The birthdate of your loved ones/friends/coworkers? Every pin code or password you use? etc…


You can memorise important dates from history and events related to it.
you can also remember and generate strong passwords.


Great suggestions!

I’m working on history, but it’s a little more complicated since it’s not just memorizing numbers but events. Passwords are a good application, though. Thanks.

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Interesting idea.

When you run out of numbers, use the events as numbers, every word is a number, just counting the letters is one way


I’d encourage you to now move beyond just numbers. Family birthdays and anniversaries, national historical events that are meaningful to you, your country’s leaders and the years they served, etc.



As @RMBittner points out, you have 10000 years of human history to work on.

If that’s not deep enough, you can mezmerize the geological epoch, Paleozoic to Paleocene with all the sub epochs and the life forms that appeared.

The world can be understood through numbers. There’s no shortage of numbers and stats that describe the world we inhabit.

In science there’s the Periodic Table of Elements, the Standard Model of Particle Physics and a whole series of constants , speed of light, grav. constant, Planck’s constant, electronic charge etc. Numbers define the very structure of Existence

In Geography you have useful stats like population, average age, life expectancy, infant mortality, gdp, major exports, military expenditure, crime rate, traffic fatality rate, literacy etc. Interesting to know that Russia’s economy is about the same size as that of Spain, the whole continent of Africa has a GDP about that of Italy. Numbers are revealing.

If you are interested, there’s endless stats available in sports, although IMO, a lot of that is junk.

Military postures: Defense spending, size and balance of various armed forces, their deployments, dates and histories of engagements. Missile and aircraft ranges etc… The US has 11 full length nuclear carriers. I believe no other country has even one. There are short deck ‘ski jumps’. The Russians have one deisel clunker that needs 6 months out fhe the year in maintenance.

In Astronomy, the Universe is described mostly by distances. Size & age of the Earth, the Moon, the Sun, the various planets and their distances to the Sun. It takes about six hours for sunlight to reach Pluto, 8 minutes to Earth and about 4 years to the nearest stars, Proxima Centauri. The size of the Milky Way. Age of the Universe… IMO this is basic general knowledge about where you live, who you are and what’s out there. Everyone should know that stuff.

The multiplication table to 25 or even 100.

I like to collect social stats and annoy people with the facts: More people in the US are killed by dogs or peanuts every year than by terrorists. The toll in school shootings pales in comparison to the number of American children murdered by their own families. The US highway fatality toll is about 45,000 every year. That’s about the death toll from 9/ll every month! … whatever your bent or subject. It’s my experience that people talk an awful lot of rubbish and having a few solid facts on the subject of interest can bring things back to reality. Doesn’t win friends but it can stop some really stupid conversations.

Major wars and their casualty tolls. Major epidemics, even more deadly than wars. Major Anthropogenic Disasters (an interesting Wikipedia entry). Leading causes of shortened life expectancy - tobacco kills 10x more people than do homicides every year. Until recently, the number of people killed by interpersonal violence was a small fraction of the number of women who died in childbirth every year. Numbers can bring surprising insights.

An excellent source of numerical information, and just fascinating browsing is the Economist’s Pocket World in Figures. Even an old copy is interesting for comparisons. The Danes drink more beer than the Swedes, even though they like to characterize the Swedes as drunk tourists. At one time the Australians were #1 in violent assaults (this is highly dependent on the country’s reporting).


You make a strong case for homicide.

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Wow, thanks so much for this thoughtful response. Lots of good stuff here. Do you use memory palaces for all of those random statistics you point out? If so, do you keep them all in the same palace?

I use random number generators to practice remembering numbers. This is one of the sites that I use: http://numbergenerator.org/random-20-digit-number-generator


If you haven’t seen it, there is a memory training tools page here that includes several generators like this random number generator.

@JS0452 @Josh

I think @bpinkall wanted some ideas on numbers he could use in life rather than random numbers :slight_smile:


For temporary information, or on the fly, I use real places for Memory Palaces or Journeys. For information that I want to own, I prefer to construct my own imaginary palace - I almost always do some kind of sketch or diagram and keep that on file. If possible, I prefer to delay construction of the memory container until I feel I can organize the material. There’s a lot of different approaches. Others encode it almost raw form and interpret it later. Sometimes you have to know stuff before you can understand it. Some people reuse the same Palaces quite heavily. With practice you find what suits you best.

I have a Palace for the Standard Model, another for the Javascript Object model. I memorized the squares up to 100 as a Journey but after some practice, I don’t have to traverse the chain, I can go directly to the number I want.

The Solar System can serve as its own Memory Palace and, with the sun and nine planets, can be used a 10 space Palace for other information too. Yes! Nine planets There is Deep Space Conspiracy among the Democratic Astronomers but justice will be done and Pluto will be restored to its rightful place among the planets…uh…where was I.

In the examples I gave above, the inferences and interpretations are my own and I don’t expect others to think that way. But the point is that there is surprising interest in these stats if you think about them a bit and opinions supported by real facts are not so easily dismissed - to challenge them one must confront those actual facts or bring others and there will be a real conversation not just a cloud of competing opinions.



Oh, sorry. I read the beginning and the end of the post at different times and only read the last comment on the second visit. I should have looked more closely. :slight_smile:

Become a human calendar.
Use the “Person” part of your PAO to memorize all the year codes 00-99.
Then a bit of modular arithmetic can give you the day of week for any date in history.

This site has a wonderful explanation along with interactive games for each stage:

Wow, I’m surprised how easy this is. Not the most practical trick to know, but a good party trick for sure. Thanks!