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Research is used to unlock technologies.

Research slots[edit]

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, democratic Germany: 4 slots, plus 2 additional possible via national focus. (Democratic Germany requires Waking the TigerWaking the Tiger).
  • Non-democratic Germany, Italy, Japan, United Kingdom: 4 slots, plus 1 additional possible via national focus.
  • France, Soviet Union, most other countries in Europe, plus Canada: 3 slots, plus 2 additional possible via national focus (in Canada's case, the last 1 requires independence).
  • Other countries outside of Europe as well as Luxembourg, Bulgaria and Albania: 2 slots, plus 3 additional possible via national focus (for British subjects, the final 2 also require independence).
  • New Zealand: 2 slots, plus 4 additional possible via national focus. (Requires Together for VictoryTogether for Victory).

For most countries, unlocking the final research slot requires having a substantial number of factories (usually 50+). The Commonwealth countries must (with Together for Victory) additionally become fully independent to maximize their available research slots.

Each research slot can store 30 days of research while unused.

Research time[edit]

Each technology has a base time cost:

Cost (days) Techs
42 Armor Submodels
85 Artillery (II) & Upgrades (II,III,IV); Anti-Air Artillery (II,III) & Upgrades; Rocket Artillery (II) & Upgrades; Anti-Tank Artillery (II,III) & Upgrades
Support Equipment; Carrier Airplanes; Electronic Mechanical Engineering; Encryption
127 Infantry Weapons (I) & Upgrades (I,III); Support & Anti-Tank Weapons; Motorized Rocket Artillery;
Marines (II), Mountain Infantry (II), Paratroopers (II)
Support Companies (II,III,IV); Artillery (I) & Upgrades (I); Anti-Air Artillery (I); Anti-Tank Artillery (I)
Shiphulls (I); Transports (I); 1st Land Doctrine; 1st Air Doctrine
Radio; Radio Detection; Decimetric Radar (I); Decryption; Experimental Rockets; Rocket Engines (II,III)
Machine Tools (I,II); Equipment Conversion; Oil Processing; Rubber Processing
170 Infantry Weapons (II,III) & Upgrade (II); Night Vision (II); Motorized & Mechanized (I,II);
Marines (I,III), Mountain Infantry (I,III), Paratroopers (I,III); Special Forces Programs
Support Companies (I); Artillery (III); Rocket Artillery (I); Great War Tank, Light, Medium & Heavy (I) Armor
Shiphulls (II,III,IV); Transports (II,III); Naval Doctrines
Decimetric Radar(II); Rocket Engines(I); Jet Engines
Machine Tools(III); Production Line (I); Industry; Construction; Excavation
212 Night Vision (I); Modern, Super Heavy & Heavy (II,III) Armor; Centimetric Radar; Computing; Production Line (II)
255 Mechanized (III); Air doctrines (not 1st); Naval doctrines; Fuel Refining
382 Land doctrines (not 1st)
425 Nuclear technology

Research speed[edit]

The base research cost only represents an abstract number of days the research will take. In practice, due to modifiers, research will progress by more or less than exactly one research-cost-day per day. All modifiers stack additively.

The research speed is calculated every day for each slot, so changes in research speed (except limited-use bonuses) apply to all ongoing research as well. The research speed can not fall below 10% of the default speed.

Research modifiers[edit]


The player can get a research speed bonus or penalty depending on the game difficulty setting as follows:

  • Civilian +15% bonus
  • Recruit +7% bonus
  • Regular no bonus or penalty
  • Veteran -15% penalty
  • Elite -30% penalty

Trade law[edit]

Main article: Ideas#Trade_laws

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

Modifier Free Trade.png
Free Trade
Export Focus.png
Export Focus
Limited Exports.png
Limited Exports
Closed Economy.png
Closed Economy
Resources to Market 80% 50% 25% 0%
Factory Output 15% 10% 5%
Dockyard Output 15% 10% 5%
Construction Speed 15% 10% 5%
Research Speed 10% 5% 1%
Civilian Intel to Others -40% -20% -10%
Navy Intel to Others -20% -10% -5%
Prerequisites One of the following must be true: One of the following must be true:

Technologies that increase research speed[edit]

Technology Year Research
Electronic Mechanical Engineering 1936 +3%
Mechanical Computing 1936 +4%
Computing Machine 1938 +5%
Improved Computing Machine 1940 +8%
Atomic Research 1940 +4%
Advanced Computing Machine 1942 +8%

Limited-use bonuses[edit]

Available limited-use research bonus automatically get activated when an applicable technology gets selected for research. The bonus is then tied to this technology and research slot. A research bonus can alternatively or simultaneously be an ahead-of-time bonus, which reduces the time span until the tech becomes current by the stated amount. This reduces the ahead-of-time penalty (see below).

Unlimited bonuses[edit]

Various national ideas, like designers, theorist, and concerns continuously improve the research speed for applicable technologies while they are active. Design companies can additionally improve equipment being unlocked while they are active.

Equipment licensing[edit]

When licensing equipment from another country, researching that equipment gets a speed bonus of +20%.

Technology sharing[edit]

When a country is part of a research group, it gets a research speed bonus for each other country in the group that has already unlocked that technology, up to +50%. Subjects benefit less from technology sharing, depending on their autonomy level.

Ahead-of-time penalty[edit]

Most technologies (except doctrines) have a date attached to them when they become current. Researching them earlier comes at the cost of reduced research speed. Each year ahead adds +200% to the ahead-of-time (AOT) penalty (e.g: 365 days ahead of time would make a research take 3 times longer than normally; 730 days ahead, 5 times as long). As the research speed is re-calculated every day, the speed penalty slowly goes down even while a technology is being researched (so starting 365 days ahead would still finish the research earlier than if you wait for the right year, but the research itself will take longer).

Ignoring other speed modifiers a technology starting to research X years before the date it becomes current, with a base research cost of N days will take . This assumes the research starts with a speed higher than the minimum and finishes before the technology becomes current. Other speed modifiers change this duration linearly.

Just below is a small python code to calculate the time it will take to research a technology, given its base cost, bonuses and AOT penalty.

res_perc = 0.0
time = 0
base = 170      # Base Cost
bonus = 0.34    # Research Speed Bonus
aot = 0.47      # Ahead-of-time penalty (not years ahead)
base /= 1+bonus
while res_perc<1:
   res_perc += 1/base/(1+aot)
   aot -= 2/365
   if aot<0: aot = 0
   time += 1
print(time)     # Prints total time needed


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.

It is possible to research improvements of already researched technologies. There could be small buttons on technology (e.g. possibility to operate from carriers for airframe). These improvements have to be researched separately.


  • 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. There are no ahead of time penalties of doctrines.

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