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Research is used to unlock technologies.

Research slots

Technology is unlocked by assigning a research slot to it for the required number of days.

The base number of research slots depends on the country tag:

  • USA: 4 slots, plus 2 additional possible via national focus.
  • Germany, Italy, Japan, United Kingdom: 4 slots, plus 1 additional possible via national focus.
  • France, Soviet Union: 3 slots, plus 2 additional possible via national focus.
  • Other countries in Europe: 3 slots, plus 2 additional possible via national focus.
  • Other countries outside of Europe: 2 slots, plus 3 additional possible via national focus.

Each research slot can store 30 days of research while unused. Additionally, the 5th research slot require a certain number of factories to be unlocked for all countries that start with 3 or less research slots.

Research time

Each technology has a base time cost:

Cost (days) Techs
50 Armor submodels
100 Artillery except for years 1934, 1936, and the first rocket artillery
Electronic Mechanical Engineering, encryption techs
150 Artillery years 1934 and 1936
Carrier submodels
First air doctines
Radio, Radio Detection, Decimetric Radar
200 Armor models except for Heavy II, Heavy III, Modern
Air models
Air doctrines after the first
Improved Decimetric Radar, Rocket Engines, Jet Engines
250 Computing

This is then modified by general and specific research time modifiers:

General modifiers

These apply to all techs, or all techs within a category.

  • Trade law
  • Computing machine technologies
  • Ideas

Specific modifiers

These apply to specific techs. Note that the sum of these stacks multiplicatively with general modifiers. Modifiers are computed when a tech starts researching.

  • Ahead of time penalty: +200% per year.
  • Research bonuses: These are generally gained via national focus. Usually a -50% modifier to a tech or a -100% ahead of time penalty.
  • Research and Production: Under Political, various designers, concerns and theorists can provide -10% or -15% bonus to research.


Technologies allow countries to unlock production of new units such as mechanized infantry, paratroopers, tanks and all kinds of airplanes; new equipment, from infantry weapons to carrier air groups and specialized armored units; as well as defensive and productive structures.

On the other hand, most technologies serve to improve the efficiency of current units. This can be achieved through a number of ways, such as improving the damage inflicted by the unit, its ability to penetrate the armor of armored units, its defensiveness and organization or simply its ability to detect enemy units.


  • Infantry technology: Technologies that improve infantry weapons and equipment, unlock or improve motorized and mechanized units as well as special forces (marines, mountaineers and paratroopers).
  • Artillery technology: Technologies that unlock and improve all types of artillery, including anti-tank, anti-air and rocket artillery.
  • Support Battalions technology: Technologies that unlock and improve all types of support battalions: Engineers, Reconnaissance, Military Police, Maintenance, Field Hospital, Logistics and Signal companies.
  • Armor technology: Technologies that unlock all types and models of tanks, from light to super heavy chassis, as well as their variants: tank destroyer, self-propelled artillery and self-propelled anti-air.
  • Land doctrine: Unlocks one of the four land doctrine trees: mobile warfare, superior firepower, grand battleplan and mass assault.


  • Naval technology: Technologies that unlocks or improve all kinds of ship units: destroyer, cruisers, battleship, carrier, submarine or improve transports for naval invasions.
  • Naval doctrine: Unlocks one of the three naval doctrine trees: fleet in being, trade interdiction and base strike.


  • Air technology: Technologies that unlock or improve all types of airframes: light, medium or heavy, as well as their jet propulsion versions.
  • Air doctrine: Unlocks one of the three air doctrine trees: strategic destruction, battlefield support and operational integrity.



All doctrines listed above serve to improve units in a specific role by providing them one or multiple bonuses once the doctrine has been researched. Some of these bonuses can be obtained through more than one doctrine, but at different depth of the doctrine tree and most bonuses are unique to a specific doctrine.

It's also necessary for all players to make a choice when researching doctrines, as opposed to all other technologies (with the exception of Industry) that can be entirely researched. Only one doctrine can be researched out of three or four options, depending on the doctrine type (land, naval or air).

It's possible to change doctrine throughout the game, but all bonuses from the old doctrine are lost, as if completely abandoned, when starting research of a different doctrine tree.