Review: MathHammer (Mobile App)

Cadian Shock has been a long time IG-centric blogger, and a hobbyist I’ve been following for a long time. But more recently, he’s become a purveyor of various Warhammer-related web and mobile apps. One of them is MathHammer, which does what it says on the tin: It’ll crunch the numbers for you.

But how well does it do at it?

First, a disclosure. I was provided with my copy of MathHammer for free in order to review it. I’d like to say this hasn’t influenced my review, and given the low cost of the app I likely would have picked it up to review anyway, but it’s something to keep in mind.

What is MathHammer?

In a general sense, the concept “MathHammer” is sitting down and calculating the expected outcomes of your games using the rules of probability. A model with two shots at a BS of 4+ should hit with 1 of them, and it it wounds on a 4+ should wound with 0.5 of them. Which means you have a 50/50 chance of dealing a wound (ignoring armor saves and the like). Now do that for squads, whole units, add special rules, etc. While in principle this is relatively simple, it’s also a hassle, and exactly the type of thing that it would be handy to have a computer do for you.

And it would be really nice if that computer was in your pocket. And didn’t rely on having an internet connection in a crowded event hall where everyone is already slamming the dubious Wi-Fi uploading things to Best Coast Pairings.

Enter the MathHammer App. Which I’m going to denote with an italic when I’m talking about the app, not the concept.


The app itself is relatively simple. First, you build yourself some profiles, or use a few of the built-in ones.

This introduces the first quirk of the app. The attacker profiles are for units, while the defender profiles are for models. A relatively recent update to the app notes this, but it’s ever so slightly unintuitive. There’s options for many potential special rules – modifications to hit and wound rolls, re-rolls, changes to AP or damage on a 6+, extra mortal wounds, etc., and as time has gone on this list has grown. It’s a good illustration of one of the problems I’ve been having with 8th Edition 40K – the modifiers have grown tremendously, and with aura abilities and the like become hard to pin down what exactly “A unit” is. But that’s hardly the apps fault, and this does a good job of it.

Once you’ve got some profiles loaded up, you have the choice of sort of a broad, “all comers” throwdown analysis…

…which might be useful if you’re comparing baseline troops choices, etc., and which can give you a good overall picture (1W 3+ save models of moderate price are the Dire Avenger ROI wheelhouse, for example). Or, you can dial in for a more specific look at a unit v. unit matchup.

What I like about this is that it walks you through the whole thing – how many hits you do, how that converts to wounds, saving throws – and in this case, how many of those are from Bladestorm, and total damage, as well as the critical note of how many actually dead models result – an important thing as a wounded Primaris Marine is just as effective as an unwounded one, and will kill your poor Space Elves dead when they return fire. There’s also a module to turn the wounding, etc. mechanic to Kill Team for that particular game and the more varied results that can emerge from it.

As I said in the beginning, the app does what it says on the tin.


Support for the app has been, in my experience, pretty solid, even ignoring any direct interaction with the developer. The built-in profiles are most of the ones I’d expect people to use, especially as defenders (MEQs, GEQs, Primaris, Knights, etc.). It also includes a solid tutorial to walk you through what’s happening, which was welcome and unexpected. I have a lot of abandoned gaming-centric apps on my phone where I sort of goofed around blindly for awhile before deciding this wasn’t worth the time to figure out.

The app is also being updated constantly. It’s gone through several updates while I was working on this review. Which is awesome to see, as when GW introduces new rules, etc. it’s important to have active development going on, as unlike a spreadsheet or pen and paper, you can’t just do it yourself.

The Place for MathHammer

Here we’re going to talk about the concept, as well as the app. I talked to Adam Abramowicz back in the day in an early episode of The Best General about when MathHammer comes into play – and given the app provides you the ability to do complex fraction-based multiplication in your head, it’s relevant to this discussion.

Should you be using it at the tabletop, to decide whether or not to shoot X unit or Y unit? I’d argue no, the time for theory has passed, and you should have a good enough idea of what your army does that you don’t need it at that point. It also slows things down, and especially in a competitive setting, slowing things down isn’t cool.

Should you be using it to grouse about how the dice screwed you, and “statistically, I should have won…” Also no. The weakness of the kind of math MathHammer is based on is that it relies on averages. Over thousands of dice rolls, the performance of a random system (like a wargame) will start to be the average result (this is known as the Law of Large Numbers). Over tens of dice rolls? Probably not. Over a single armor save? Definitely not. Variance is a thing (hence this blog).

What you should be using MathHammer for is helping you build heuristics for what your forces can and cannot do. What you can expect them to do, even if you can’t rely on it. If I expect that unit of Dire Avengers to be able to scythe down a Primaris Marine squad? The math tells me there’s only an outside chance of that happening. It’s a way to figure out if that “anti-infantry” option for a tank is actually better at killing infantry, or just more shots that will be less effective overall. A way of figuring out which units are really boosted by being in a re-roll hit or wound aura, and which ones are largely stand alone.

And for all of those purposes, I think the MathHammer app is the tool for the job.

Overall Rating: A

MathHammer is available for iOS on the App Store and for Android on Google Play.

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