Warhammer 40000 Probabilistic Damage Calculator

WH40K probabilistic damage calculator by andresgongora

There are many damage calculators out there for WH40K, however, they all oversimplify things to get a quick but innacurate damage estimate. This estimator relies on probability mass functions to propagate the exact damage from the moment you roll the number of shots all the way to invulnerable saves. Guessing which weapon is the best or what unit you should attack with it is a thing of the past.

Follow this link to the damage calculator, or continue reading down below for instructions and further information.


Under the hood

For simplicity, and so that you can check the damage calculator almost anywhere, I've written it in Google Sheets. In particular, I use Google Sheets for data visualization and simple calculation, and rely on its JavaScript support to call more advanced functions. For the curious, the later a function that compute the probability mass functions of D6 dices and the Bernoulli distribution, among others, and compute they convolution (something like a everyone-with-everyone product) to compute the exact probability for each possible outcome.

For simplicity, and so that you can check the damage calculator almost anywhere, I've written it in Google Sheets. In particular, I use Google Sheets for data visualization and simple calculation and rely on its JavaScript support to call more advanced functions. For the curious, the later a function that compute the probability mass functions of D6 dices and the Bernoulli distribution, among others, and compute they convolution (something like an everyone-with-everyone product) to compute the exact probability for each possible outcome.


How to


1. Select the mini for which you want to calculate its damage output. To do so, simply chose the faction it belongs to, and then the name of the mini. The window should change to a picture of said mini (all images belong to Games Workshop and are linked externally), and its stats.






2. Select the target you want to attack. You can add up to 10 different target minis (plus 2 custom ones) to compare the efficiency of your weapons side-by-side.






3. Select the type of base statistic you want to compute (by default set to average) and the type of wounds you want. You will also see a list of the weapon options available to your mini, and get the opportunity to add your own custom weapons at the bottom. The available options are:
  • Wounds: as the name implies, how many wounds you will cause to a targeted mini.
  • Effective wounds: the same as wounds, but accounts for the target's life. So, causing 8 wounds to a simple marine is clearly an overkill, and said figure will be capped to give you a realistic representation of how effective it really is.
  • Kills: how many minis of the target type will be removed from the table, accounting for their wounds and such.
  • Kill points: instead of how many minis are removed, it tells you how many points your opponent player has lost.







4. Observe the overall statistics for each weapon and each target mini. Here it becomes super clear that weaker units are very vulnerable to weapons such as flamers, but that shooting heavies on them can be a bit of a waste.






5. Finally, observe the exact probability mass function for the weapon and target of your choice. Can't decide whether to go with cannons or lasers? Here is where you have to look at. Notice that the left-most column in the chart represents the probability of causing 0 damage when firing the weapon of your choice and that all other columns to its right represent the probability for all other possible outcomes.





FAQ

  • Why did you do this? I'm working with probabilistic tools all day long, so I thought it could be fun to apply them to a game just for fun (I'm a nerd, I know). Also, the world really needed a probabilistic damage calculator for a tabletop game. There was no way we could go any further without it, and deep down you know it.
  • There is an error. Quite likely. There is a lot of script code in this sheet, so mistakes are bound to happen. If you notice anything, please let me know and I will fix it promptly :) 
  • My mini/faction/weapon is not listed. Sorry about that. So far I could only add a few of my own minis and those of my friends. But you are free to add your own. I've enabled comments in the sheet, so you should be able to add any data you wish as "suggestions" which I will gladly accept.

1 comment :

  1. Anonymous10/2/23 14:37

    when ww3 comes this app is necessary

    ReplyDelete