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This is a reference guide describing how the production system works.

Production costs and build times are determined by applying a modifier to the base cost and time for units or buildings. The actual base costs can be found in Reference. There six different modifiers that are added together to give a total modifier. These sub-modifiers are:

  1. Practical Knowledge: Modifies the time and cost of unit production.
  2. Industrial Efficiency: Each level of the Industrial Efficiency tech will reduce the cost and time by 2.5%.
  3. Upgrades: Every tech that modifies the base statistics of a unit (speed, soft attack, organisation, etc.) will increase the unit's cost and time by 1%. This does not include the tech that allows the building of the unit but does include doctrines, if they modify the unit's statistics.
  4. Industrial Policy: Law, which affects IC costs and build times.
  5. Training Law: Only affects the build times of units and not costs or building cost/time.
  6. Reserves: Reduces the IC cost and manpower cost but time is unaffected, reduction is dependent on conscription laws.

Industrial Capacity (IC)

On the Information Bar, fifth from the left, you will see a factory symbol and three subdivided numbers, which represent your Industrial Capacity (otherwise knownas “IC”) e.g. 12/47/25. The first number is Wasted IC – it is IC that you could be using but you’re not (and, of course, you’ll want to fix that). The next number, on the other side of the first slash, is the Available IC – how much Industrial Capacity you actually can use. The last number, to the right of the slash, is the Base IC – how many “factories” (factory points, really) your country has, which make up the bulk of what becomes the Available IC. Each effective IC must consume 2 units of energy, 1 unit of metal, and 1/2 unit of rare materials every day to continue operating. Not having enough will reduce effective IC until it consumes just what is produced


IC-days is a formula for accurately determining the total cost of unit production. This formula provides data required in order to make long term production planning decisions.

IC cost * build time = IC days

For example, an Infantry brigade (assuming no Practical Knowledge bonuses) costs 2.33 IC to produce, and will require 95 days to complete. Stated another way, this means those 2.33 IC are being exclusively used for a period of 95 days. Thus, the real IC cost for the Infantry brigade is actually (2.33*95) = 221.35 total IC. This term is used frequently by players when comparing the value of different builds.


The exact formula for the cost of upgrades is unknown but some general observations can be made.

  1. The Upgrade cost and time are affected by all the factors that affect a new build (Practical Knowledge, Industrial Efficiency, Number of Upgrades, Training Laws).
  2. Upgrading a unit two techs out of date costs 50% less than the one that upgrades the unit to the current tech level. The assumption is that it is like HoI2, each one was 50% of the previous: 100% for current upgrade, 50% for one out of date, 25% for two out of date, etc. Obviously, the most out of date tech is the first to upgrade.
  3. The time for an upgrade is approximately 25% of a comparable new build. Capital ship upgrades seem to be an exception, taking somewhat longer. Times are unaffected for upgrades more than one tech out of date.
  4. It appears to actually be cheaper to build a unit and then upgrade it as opposed to waiting until a tech is complete and then building an up to date unit. This may change at extremely low Practical Knowledge levels but unlikely a player will have levels approaching zero when they upgrade units.
  5. Doctrines that increase new unit build costs/times do not have any Upgrade costs and completed in one day (one day for each level, if multiple doctrine levels need upgrading). If a unit is set to not upgrade any doctrines will also not upgrade.


A player wants to build an Infantry brigade. Infantry Practical knowledge is at 10.0 (+12%). The player has researched all four sub techs in the Infantry tab to 1940 (level 4) as well as the Infantry Warfare Land Doctrine to 1938 (level 2) (total -18%). Industrial Efficiency tech is at 1938 (level 4) (+10%). Finally, the player has selected the Specialist Training law (-20% in build time). The unit is not a reserve. The total cost modifier is 12-18+10= +4% (decreased cost of 4%). The build modifier is 12-18+10-20= -16% (increased build time of 16%). Base values for an Infantry brigade is 2.33 IC and 95 days so the actual values are 2.24 IC (2.33*0.96) and build time of 110 days (95*1.16). These may vary slightly due to rounding errors.