Chance is generally represented as a percentage, a fraction, or a decimal; like 16%, or 1/8, or 0.58. This is the statistical likelihood of something happening, or not happening.

For example:
A die has a 1/6 chance of rolling a One. That’s 16.67%, or 0.167 [rounded]; in reality it’s 16.6∞%, and 0.16∞
What this means: Each time you roll the dice, you have a 1/6 chance that the number will be a One.
What it doesn’t mean: You are guaranteed to roll a One in every Six rolls. Unfortunately this doesn’t happen.

So why isn’t it guaranteed One in every Six???

Theory vs Reality
1/6 is the theoretical statistical chance of rolling a One. It is the “perfect world” scenario. In reality, the world is not perfect, variation occurs in every microsecond, and every roll is different.
However, if you roll a die a very large number of times then you will start to see an average in the results of each number having a 1/6 (or close enough) representation.

In reality you also have the chance of never rolling a One. As well as the chance of always rolling a One. Those chances are infinitesimally small, but they exist. You could also manage to roll all the numbers in order, from One to Six. Infinite possibilities, not all with the same chance, but all existing.



Notes: ~ means approximately, so I’ve rounded the number into a nice number (tens and fives) further than just rounding up or down a decimal. E.g. 0.485 becoming ~50% instead of 49%.

Adventuring Business Cards
Business cards have a 1/8 [0.125] chance of dropping every time you defeat the final boss. There is also a 1/8 chance that this drop slot is taken by one of the other seven Adventuring Boss Exclusives [Ids 2881-2887]

What are the chances?
[for at least one card received during a number of adventuring runs]

In one run, you have a 12.5% [1/8] chance of receiving a card. This means a 87.5% [7/8] chance of not receiving a card.

In five runs, you have a ~50% [0.487] chance of receiving a card. This means a ~50% chance of not
receiving a card.

In eight runs, you have a 66% [0.656, ~2/3] chance of receiving a card. This means a 34% [~1/3] chance of not receiving a card.

In ten runs, you have a ~75% [0.737] chance of receiving a card. This means a ~25% chance of not receiving a card.

In fifteen runs, you have an 87% [0.865] chance of receiving a card. This means a 13% chance of not receiving a card.

In twenty runs, you have a 93% [0.931] chance of receiving a card. This means a 7% chance of not receiving a card

In thirty runs, you have a 98% [0.981] chance of receiving a card. This means a 2% chance of not receiving a card.

Forty runs is a 99.5% chance, Fifty is a 99.8% chance. This still leaves a 0.5% and 0.2% chance of not receiving a card in those runs.

No matter how many times you go through adventuring, there is Never a 100% chance of getting a card from the boss. It will get so close that it’s almost indistinguishable from 100%, but there will always be a teeny tiny chance of not getting a card.

Nestor Cat Adoption
Every day, you are able to visit Nestor at the Meeting Grounds and he offers you an item. Sometimes that “item” is a not-cat. The chance of the “item” being a not-cat is 19%, not quite 1/5.
Nowadays, on the seventh day of not receiving a not-cat you automatically get offered one from Nestor. You don’t have to accept, but the offer is guaranteed.
Before guaranteed not-cats, it was solely chance based.

What are the chances?
[for receiving at least one not-cat from Nestor at the Meeting Grounds]

In one day, you have a 19% chance of receiving a not-cat. This means a 81% chance of not receiving a not-cat.

In two days, you have a 34% [0.344] chance of receiving a not-cat. This means a 66% chance of not receiving a not-cat.

In three days, you have a ~50% [0.469] chance of receiving a not-cat. This means a ~50% [0.531] chance of not receiving a not-cat.

In four days, you have a 57% [0.57] chance of receiving a not-cat. This means a 43% chance of not receiving a not-cat.

In five days, you have a 65% [0.651] chance of receiving a not-cat. This means a 35% chance of not receiving a not-cat.

In six days, you have a 72% [0.718] chance of receiving a not-cat. This means a 28% chance of not receiving a not-cat.

In seven days, you have a 77% [0.771] chance of receiving a not-cat. This means a 23% chance of not receiving a not-cat.

On day seven of no not-cats you are guaranteed one, but I’m also gonna give you the chance over more days because it used to be important XD

In ten days, you’d have a 88% [0.878] chance of receiving a not-cat. This meant a 12% chance of not receiving a not-cat.

In fifteen days, you’d have a ~95% [0.958] chance of receiving a not-cat. This meant a ~5% chance of not receiving a not-cat.

In twenty days, you’d have a 98% [0.985] chance of receiving a not-cat. This meant a 2% chance of not receiving a not-cat.

In thirty days, you’d have a 99% [0.999] chance of receiving a not-cat. This meant a 1% chance of not receiving a not-cat.

Letters from Travelling Cats
When you send not-cats travelling, they have a 1/16 [0.625] chance of sending home a letter to your village. You can currently send up to 216 [max] not-cats travelling, though this may increase with later updates. Each not-cat you have travelling will roll this 1/16 chance when you Get Mail, so the more not-cats you have out, the more chance of you getting mail. The base maximum number of letters you can receive is nine.

You can also assign a Mail Carrier, who will change your chances and the maximum amount of mail you can receive. I’ll look at the least effective mail carrier, best mail carrier with no bonuses, best with trinket, and the very best which is currently unattainable.

The Mail Carrier calculations are as follows:

Village Lodge Page Says

Agility: 17-19 [+5%], 20-22 [+10%], 23-25 [+15%], 26-28 [+20%], 29+ [+25%]
Extroversion: 8-10 [+4%], 11-13 [+8%], 14+ [+12%]

The least effective MC [mail carrier] would only give a 4% increase to chances [Extroversion 8-10, less than 17 Agility]. This would increase the chance from 0.0625 to 0.065, which is 6.25% to 6.5%. The maximum amount of mail you can receive then goes from 9 to 10 [9 to 9.36, but PCE always rounds up]

The best no-bonus MC would have 23-24 Agility [15%] and Extroversion 8-10 [4%] leading to an increase of 19%. This would increase the chance from 0.0625 to 0.0744, which is 6.25% to 7.44%. The maximum amount of mail you can receive then goes from 9 to 11 [9 to 10.71]

The best trinket boosted MC would have 23-24 Agility [15%] and Extroversion 11-13 [8%] leading to an increase of 25%. This would increase the chance from 0.0625 to 0.0781, which is 6.25% to 7.81%. The maximum amount of mail you can receive then goes from 9 to 12 [9 to 11.25]

The very best MC would have 29+ Agility [25%] and Extroversion 14+ [12%] leading to an increase of 37%. This would increase the chance from 0.0625 to 0.853, which is 6.25% to 8.53%. The maximum amount of mail you can receive then goes from 9 to 13 [9 to 12.33]

What are the chances?
[for at least one letter with No mail carrier bonus from a number of travelling not-cats]

With one traveller, you have a 6% [0.0625] chance of receiving a letter. This means a 94% chance of not receiving a letter.

With five travellers, you have a 28% [0.276] chance of receiving a letter. This means a 72% chance of not receiving a letter.

With ten travellers, you have a ~50% [0.476] chance of receiving a letter. This means a ~50% chance of not receiving a letter.

With twenty travellers, you have a 73% [0.725] chance of receiving a letter. This means a 26% chance of not receiving a letter.

With thirty travellers, you have a ~85% [0.856] chance of receiving a letter. This means a 15% chance of not receiving a letter.

With forty travellers, you have a 92% [0.924] chance of receiving a letter. This means a 8% chance of not receiving a letter.

With fifty travellers, you have a 96% [0.96] chance of receiving a letter. This means a 4% chance of not receiving a letter.

With one hundred travellers, you have a 99% [0.998] chance of receiving a letter. This means a 1% [0.002] chance of not receiving a letter.

To display the differences and increases in the chances of receiving at least one letter when you have different Mail Carrier bonuses, I have made a table

I have also added the column showing the “Maximum Chance Increase”, which is the difference in chance between the base chance, and the very best mail carrier chance.

Stat Increases for Students
By building the Village Lodge and then the Schoolhouse, you can then assign a Teacher. The Teacher unlocks the ability for Kittens and Adolescents (not Young Kittens) to perform the Daily Task of a Student. The Student job gives a chance for the not-cat to increase +1 in a stat.

Students have a maximum of 56 days to try getting stat increases, and there is no limit on how many they can get.

The Teacher calculations are as follows:

Village Lodge Page Said

Base odds of stat increase are 1 in [50 - CLEVERNESS - BENEVOLENCE]. Student's dedication will be subtracted from this. Odds cannot exceed 1:9.

Please Note: For anyone familiar with Ratios, the 1:9 ratio is a Chance ratio, not a Measurement ratio. Meaning it is 1 in 9, similar to 1/9, not 1 to 9 (1/10 to 9/10).

The worst Teacher you could get would be 4 Cleverness and 0 Benevolence, giving you only 1/46 [2.17%] chance of an increase.

Let’s say an Average Teacher (one you’d be happy to have as a Teacher) has 18 Cleverness and 7 Benevolence. 50 - 18 - 7 = 25, so a 1/25 [4%] chance of a Stat increase, and that’s before you consider the Student’s dedication.

An Average Teacher with a Great, 10 Dedication Student could raise those odds to 1/15 [6.67%].

And of course the Very Best chance of a Stat increase is 1/9 [11.1%].

What are the chances?
[for an Average Teacher to give a Student at least one Stat increase over a period of Kittenhood to Adulthood]

In one day, you have a 4% [0.04] chance of getting a Stat increase. This means a 96% chance of not getting a Stat increase.

In five days, you have a ~20% [0.185] chance of getting a Stat increase. This means a ~80% chance of not getting a Stat increase.

In ten days, you have a ~35% [0.335] chance of getting a Stat increase. This means a ~65% chance of not getting a Stat increase.

In twenty days, you have a 55% [0.558] chance of getting a Stat increase. This means a 45% chance of not getting a Stat increase.

In thirty days, you have a 70% [0.706] chance of getting a Stat increase. This means a 30% chance of not getting a Stat increase.

In forty days, you have a 80% [0.805] chance of getting a Stat increase. This means a 20% chance of not getting a Stat increase.

In fifty days, you have a 87% [0.87] chance of getting a Stat increase. This means a 13% chance of not getting a Stat increase.

In fifty-six days, you have a 90% [0.898] chance of getting a Stat increase. This means a 10% chance of not getting a Stat increase.

To display the differences and increases in the chances of getting at least one Stat increase when you have different Teacher bonuses, I have made a table

I have also added the column showing the “Average to Best Chance Increase”, which is the difference in chance between the Average Teacher chance, and the Best Teacher chance.

Reserve 3

Reserve 4

Reserve 5

Reserve 6, should be safe now

This is amazing!! I love that you’ve actually went and did the math, it’s so interesting to see the different probabilities