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Revision as of 15:01, 20 December 2016 by Neusaap (talk | contribs) (Added brief explanation about technology sharing.)
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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:

  • 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.
  • Most other countries in Europe, plus Canada: 3 slots, plus 2 additional possible via national focus.
  • Other countries outside of Europe as well as Luxembourg, Bulgaria and Albania: 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
Support Equipment
150 Artillery years 1934 and 1936
Carrier submodels
First air doctines
Radio, Radio Detection, Decimetric Radar
Infantry upgrades
Support battalion and special forces upgrades, First Air Doctrine Tech, Basic Machine Tools
200 Light and Medium Armor, Modern Air models, Air doctrines after the first
Improved Decimetric Radar, Rocket Engines, Jet Engines
Infantry equipment
1936 support battalions and special forces, Naval Doctrines, Industry, Construction
250 Computing, Heavy and Super Heavy Tanks, All Radar Techs after Radar II
300 Land doctrines, Last Motorized Tech
500 Nuclear technology

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

General modifiers

These apply to all techs.

Trade law

Main article: Ideas#Trade_laws

Trade laws can also reduce research time. The more open the trade the higher the reduction as can be seen below.

Law Resources
to Market
Free Trade.pngFree Trade 80% +15% +15% −10%
Export Focus.pngExport Focus 50% +10% +10% −5%
Limited Exports.pngLimited Exports 25% +5% +5% −1% One of the following must be true:
  • All of the following must be true:
    • At war.
    • Current ruling party is Democratic.
    • Any enemy country has more than 20% of this country's total number of factories.
  • All of the following must be true:
Closed Economy.pngClosed Economy 0%

Computing machine technologies

Technology Year Base Time
to Research
Electronic Mechanical Engineering 1936 100 -2%
Mechanical Computing 1936 250 -3%
Computing Machine 1938 250 -3%
Improved Computing Machine 1940 250 -5%
Advanced Computing Machine 1942 250 -5%

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 Companies 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.

Technology sharing

Some countries may share their technological progress with other members of the sharing group they are part of. This means that they will receive a reduced research cost for technologies already researched by other members vice versa. Sharing groups are not necessarily limited to faction. If more members have researched a technology, the the discount will be greater.

Certain sharing groups may be restricted to specific technological areas, such as electronics or radar, where others, for instance the British commonwealth, are universal in this respect.

The sharing bonus may be reduced depending on the autonomy level of a puppet nation.