RNG explained

If you are new to the game, the concept of RNG might be a bit confusing. You see a lot of numbers about your tank, and might think that “Isn’t this it?”

The simple answer is “no”.

RNG stands for “Random Number Generator”, and is implemented in the game to make it less predictable. It means that for certain data about a tank, the number will vary as much as 25%.

Type 4 Chi-To

Let’s take a look at a random tank. I will choose the Japanese Type 4 Chi-To, since I am grinding it at the moment.

Penetration

The penetration of the top gun is 155, according to tanks.gg (which I recommend). But if you check in the game, you can see that the penetration will vary between 116 and 194, which is 155 +/- 25%. The average penetration will over time will be 155, but you can get lucky or unlucky, meaning that the penetration will be higher or lower than that.

Damage

The same variation is to be expected when it comes to damage per shot. The alpha damage of the Chi-To is 130 hp, but due to RNG, you can high roll or low roll, getting from 163 to 97. This is 130 +/- 25%.

Other factors are not affected by RNG, such as reload time and the speed of your tank.

So, how do you use this information? I would suggest you ignore them, at least when you play lower tier tanks. When you play tier IX or X, you can start to play according to RNG. Let’s say your alpha damage is 390, and you see an enemy with 350 hp left, you can be reasonably certain you can kill him/her with one shot. You can take the chance of firing at him even if you expose your tank to him if you are reloaded and he isn’t.

If his remaining health is 485, you actually CAN kill him with one shot, if you high roll. But you can not expect to do so, and should play much more carefully.

A short introduction to some key phrases used in World of tanks

You may have discovered yourself, but there are some phrases in World of tanks that might seem a bit mysterious to a newcomer. I will explain a few of them here.

DPM: Damage per minute. This is a value describing how much damage you will do per minute, if you can fire at an opponent an both hit him AND penetrate his armor. It is a function of the number of shots you can fire per minute and how much damage each shot will do. (See “alpha damage” below.) The higher the number, the more dangerous your gun is to the enemy. However, DPM will often be a theoretical value, as you only rarely are able to shoot at an enemy before he moves, discover you and fire back, or some other enemy discover you and shoot at you. Because effective DPM requires you to penetrate the enemy, the penetration of your gun is very important, of course. Any value higher than 2.000 is good from tier III to tier VIII. At tier IX mediums the value should be 2.200 and above. At tier X medium: Any number higher than 2.400 is good.

Alpha damage: The amount of damage each of your shots will do to your enemy. This value is also depending on both hitting your enemy and penetrating his armor. At lower tiers the alpha damage is a lot less than on higher tiers, of course. Alpha damage is not a fixed amount, it varies somewhat from shot to shot, due to RNG (see below).

RNG: Random numbers generator. This is an effect incorporated in World of tanks to make it less “machine like”, I guess. It refers primarily to two aspects: Alpha damage and accuracy. On most (all?) guns in the game, the alpha damage varies from x to y hit points. All your shots that both hit and penetrate your enemy will do damage between x and y, and the “normal” damage will be the average between x and y. Some people claim that a specific gun on a specific tank is always closer to x or y, but I haven’t found any information supporting such a claim. (It is supposed to be random.) RNG also affects accuracy. When fully aimed, each shot should hit within the reticle (the circle you see when you aim). RNG means that the deviation from the center of your reticle will vary randomly.

Nerf: Nerf is a term used when Wargaming changes a tank in the game, due to statistical analysis from a large number of battles. “Nerfing” means they change the tank so it performs slightly worse on some key parameters, because it is considered an “overpowered” (“OP”) tank. Nerf is sometimes done to a single parameter, like alpha damage (see above) or to a number of parameters, like view range, speed or traverse speed, to reduce it’s impact on the battlefield.

Buff: This is the opposite of nerfing, by making a tank slightly better. I claimed a while back that the ARL V39 is the worst tier VI tank destroyer. Since then its gun has been buffed slightly. (It still is garbage, though.)

If there are any phrases you would like me to explain, tell me in the comment section below.