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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: 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 (n Canada's case, these last 2 also require 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
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 company 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[edit]

These apply to all techs.


The player gets -5% on Recruit difficulty and +10% on Veteran difficulty.

Trade law[edit]

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%

Technologies that reduce research time[edit]

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%
Atomic Research 1940 500 -2%
Advanced Computing Machine 1942 250 -5%

Specific modifiers[edit]

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, applied when next eligible research project starts or restarts.
  • Research and Production: Under Political, various designers, concerns and theorists can provide -10% or -15% bonus to research.Note at what point in the research project these modifiers are applied.


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). This improvements has 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. However, you are not stuck with the doctrine you begin with. Before unpausing at the start of the game you may change a pre-researched doctrine without penalty. Simply click on the doctrine right below the one that starts researched and click to research it. Now click on the starting doctrine you wish to change to and it will be researched instead.

Technology sharing[edit]

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 and 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. Commonwealth technology sharing is automatic from the start of the game. Others can access specific sharing arrangements by by national focus, or by turning on and maintaining a continuous focus if that is available. Cooperation and coordination in research can be very effective in multiplayer games.

The sharing bonus may be reduced for puppets depending on their autonomy level.