Mouse over "
[Client Values; Actual values in
|11301230 HP Hit Points|
|44.88/47.545.95/48.4 t Weight Limit|
- Commander (Radio Operator)
|600700 hp Engine Power|
|34/14 km/h Speed Limit|
|3235 deg/s Traverse|
|13.3715.23 hp/t Power/Wt Ratio|
|120/90/60 mm Hull Armor|
|100/90/90100/90/90 mm Turret Armor|
|160/160/280390/390/530 HP Damage|
|120/161/43175/217/61 mm Penetration|
|r/m 12.24 r/m 4.88 Rate of Fire|
See here, here, or here for more information.
See here, here, or here for more information.
See here, here, or here for more information.
See here, here, or here for more information.
▲1903.2 Damage Per Minute
With 50% Crew: 0.57 m
With 50% Crew: 0.57 m
|s 2.9 s 3.4 Aim time|
|3828 deg/s Turret Traverse|
|360° Gun Arc|
|-5°/+22°-6°/+25° Elevation Arc|
|6828 rounds Ammo Capacity|
|1512 % Chance of Fire|
|m 330 m 350 View Range|
|m 440 m 625 Signal Range|
The IS-1 (IS-85) heavy tank was a thorough modernization of the KV-1. The tank featured the 85-mm D-5T gun. The IS-1 entered mass production in October 1943, but work was discontinued at the beginning of 1944, as the IS-2 (IS-122) tank entered mass production in December 1943. A total of 107 vehicles were manufactured.
It is the first of the Iosef Stalin class tanks available to the player. The IS represents both the IS-1 and the early model IS-2. The IS can be researched from the KV-85 or from the KV-13, which is sometimes is used as an easy grind bridge.
The stock tank is the IS-1, equipped with the 85mm gun also available on the KV-85. The IS is a continuation of the KV-85 and will thus feel very similar in terms of agility and speed. When equipped with a 122mm gun, it technically becomes an IS-2, which will feel much more potent when engaging other heavies. Like most Soviet heavy tanks, the IS fares much better engaging enemies at close range where the IS can hug cover and back off when it is reloading. Thus, the IS is better for maps such as Himmelsdorf where there are mostly close-quarters fighting and no big open areas.
The frontal armor on the IS is adequate to bounce lower-tiered vehicles somewhat consistently and can pull off surprising bounces from higher tiered hostiles. Play this tank intelligently, choose the correct moments to fire at enemies, retreat to reload, and then unleash your gun upon hostiles once more. The IS is the exact definition of an adequately armored heavy tank that trades extreme protection (at least in World of Tanks) for mobility and firepower.
Modules / Available Equipment and Consumables
|Turret||Turret Armor (front/sides/rear)
|Turret Traverse Speed
|Chance of Fire on Impact
Pros and Cons
- The 122mm D-25T is an excellent gun for the vehicle's purpose, with 390 alpha damage and a very fast (for the caliber) reload
- Very mobile vehicle for a heavy tank, especially with the upgraded engine and it can flank enemies if need be
- Side armor of the tank is quite good at allowing side-scraping when dealing with lower-tier and equal tier vehicles
- Tricky (to the enemy) armor package, the IS can wiggle its hull to cause first fire or returning enemy fire to bounce
- The IS is an effective support tank in higher tier matches, as long as it can land shots and stay out of danger
- Unfortunately the gun is quite terrible in all other regards besides DPM and alpha damage
- The D-2 guns on the IS have some of the worst penetration values for tier VII heavy tanks and MUST be aimed carefully
- The IS has somewhat of a terrible stock grind, but it can handle itself against lower tiers even when stock
- The turret is rather horrendous overall with horribly formatted armor zones that are thin and poorly angled
- The IS has a rather prevalent front cheek plate that can completely ruin the side-scraping ability of the vehicle
In comparison with the KV-3, the design philosophy for the IS shifted away from the same structure of armored protection. As a result, the IS is one of the more maneuverable heavy tanks. While not quite fast enough to flank enemy tanks on a regular basis, this tank is terrific for "peek-a-boom" maneuvers from behind cover.
On paper, the stats for the second 122mm gun do not appear much better than the first 122mm, but the increased fire rate often makes the difference between life and death. Against higher tier heavy tanks and tank destroyers, the 122mm guns threat factors are greatly reduced, if blatantly ignored by tanks like Object 705, E 75, VK 45.02 (P) Ausf. B and Type 4. In these situations, switch to a target with weaker armor if possible. Many low tier tanks fear the IS due to its capability to one-shot some lower tier tanks. It has one of the highest "Fear Factors" among the tier VII heavies (although challenged in that regard by the O-Ni and T29 for sheer intimidation).
For a more medium tank play-style, use the 100mm "1D10T" D10T gun. It does do less alpha damage than the D-2 series guns, but it has a good rate of fire, better accuracy and better aim time, making a great scout-killer gun that can also engage at a longer range than the D-2 guns. Be aware that the T-44 tier VIII medium tank uses a similar gun as its top gun. Also, the credit cost per round is only a quarter that of the D-2 guns, making it more profitable to use, which in turn makes grinding more enjoyable. It is recommended for the grind towards the IS-3 for the more trigger-happy, as the far lower cost per round will allow you to retain credits more easily. The epitome of IS game-play is based on the D-2's alpha, allowing you to play "peek-a-boom" and survive longer. However, its poor accuracy may render the tank effectively useless at long range, with insufficient penetration to deal with enemy armor. It is unable to hit weak spots without exposing the tank for a dangerously long time, whereas the 100 mm gun can be used to target weak spots even when taking snapshots.
However, for those who stick to the course of the 122mm guns, the higher tier of the two, especially with a 100% crew and tank gun rammer, can easily be seen as a pre-9.4 KV-1S, and KV-85 skilled operator's heaven. The gun takes about 10.1-3 seconds to reload with these modifiers in place. Very few heavy tanks with similar guns will be able to fire as quickly as you can, save for the Tiger specifically. Despite the below-average penetration, the IS, with the D-25T mounted, can still lay down some serious firepower. The IS has drastically improved gun depression compared to the KV-85. Because of the decent reload speed, it is also viable to switch between rounds without endangering yourself nearly as bad as it was when doing the same with the 122mm on the KV-85.
Yet another thing to note is that the IS does not lose any of the agility from the KV-85. In fact, with the top engine, the IS enjoys an additional 100 horsepower, which improves acceleration and the ability to climb inclines. The IS can also turn its hull 5 degrees faster than the KV-85, allowing it to react quickly to emerging threats. The only major flaw with the IS's 122mm guns is the horrible accuracy and the relatively inflexible nature.
When in tier VII matches, you can subjugate the opposing team's tanks with your punishing blows and rapid-fire, especially against those that ignore the threat you pose. Keep in cover if there are SPGs present. Do not expose your tank and try to brush off the incoming fire from hostiles using buildings or terrain, especially at higher tiers. Be careful of more agile mediums and light tanks, you may be fast, but they are faster, and most can put several shots into for each you put into them. The Peek-a-Boom tactic makes the IS in tier VII a very formidable opponent, even against tanks like the T29. The Tiger I will challenge your DPM but will stand no chance against your very heaving hitting D-25T as the tier VII German's armor profile is extremely ineffective against you.
Tier VIII is deadly, although you are still relatively capable and able to compete against tier VIII tanks. Tier VIII is where the devious Waffentrager Borsig, imposing T34, frustratingly bouncy IS-6, and other deadly tanks lurk. If you are stuck in the open with any such tanks present, you will be quickly dispatched. Yet on the other side of the coin, the IS still has one ace up its sleeve: its agility. With the correct playstyle, the IS can abuse hardcover and retain hitpoints for dire situations. Tier IX will eat the IS alive (your armor, gun, and mobility are sometimes useless due to the overwhelming odds and armor you'll encounter) and the tank should be used exclusively as a support tank that can flank the much more dangerous tanks when they are preoccupied with your allies. Unfortunately, even premium ammunition contained in the vehicle (APCR; 217mms) will be barely useable for the front of higher tiered heavies, so spare use is required.
Overall the IS can be a fun and interesting tank to play, especially if you understand where enemy tanks are weakest and when to pounce on opportunities when they arise.
- Unfortunately the only usable module that carries over from the KV-85 is the 122 mm D-2-5T gun, and it is not immediately usable, so you have to fight stock for a while (unless you have unlocked the 85 mm D5T-85BM or 100 mm D10T via the medium line). The engine may also be unlocked from the ISU-152 TD line.
- Your first step should be to research the 2nd turret (if you have not done so already) in order to mount the 122 mm D-2-5T (the 1st 122mm). Alternatively, you could research the 100 mm D10T.
- Next the tracks are good for the increased traverse speed and because the engine costs so much more, it also helps to slightly improve overall agility.
- Go from there.
- Note the V-2-54IS engine, the 12RT radio, and the 122 mm D-25T gun are also upgrades on the IS-3, the more you research here, the better later, as many modules will carry over.
Development and Preliminary Design
At the beginning of Operation Barbarossa, the KV was the Soviet's Heavy tank. German tanks of the time had difficulties engaging it but after the Tiger appeared, the heavy KV proved inadequate. The tank was heavy, but poorly armed with the same gun as the much more mobile T-34 medium tank. Thus, a replacement was ordered. N.V. Tseits, recently released from a GULag, was appointed head designer of the new project.
The project first led to the KV-13 universal tank, which was supposed to have medium weight and heavy protection, with both turret and hull protected by cast armor. By sacrificing internal space, the consumption of materials was minimized for given armor protection, following instructions of the State Defense Committee's decree of 1942. The KV-13 was equipped with a 600hp engine, capable of reaching speeds up to 55 km/h, and used parts from both the T-34 and the KV. However, acceleration was poor and the tank suffered severe reliability problems. Despite improvements, the Soviet military lost interest in the project.
Despite this, the Experimental Tank Factory continued research and testing, led by N.F. Shamshuring after the death of Tseits. The design was now more based on the KV-1S. After the appearance of the German heavy Tiger tanks, the speed of development was increased and orders were placed for two Iosef Stalin (IS) prototypes, based on the design of the KV-13. One of the prototypes, the IS-1 (factory designation: Object No.233), was armed with a 76.2mm gun, the other, the IS-2 (factory designation: Object No.234) was armed with the 122mm U-11 howitzer. Both tanks had better armor protection, higher speed and equal or better armament than the KV-1S. Problems with the engine and transmission were solved while factories prepared for the production of the new vehicles.
After the first data about the German Tiger tank became available, it turned out that the 85mm AA-gun 52-K model 1939 was the most effective against its armor. It could penetrate the 100mm frontal armor from 1000m. New 85mm guns based on the 52-K model were developed, the D-5T gun ultimately being the chosen gun for further development. The IS-1 was ordered into production, together with an order for the development of an IS with a 122mm gun, based on the 122mm Field Cannon A-19 Model 1931, which proved to be the most effective anti-tank gun in the battle of Kursk. During tests, the 122mm was able to throw a Panther several meters back with a penetrating shot in its side armor. Other tests were done with a 100mm gun, but this gun was not available in large numbers and ultimately scrapped.
The first IS-1s (85mm) were produced in October 1943, the first IS-2s (122mm) in December. Production of the IS-1 was quickly stopped in January 1944, in favor of the IS-2. Only 107 IS-1s would be produced.
In combat, the 122mm with regular sharp-nosed APHE ammunition did not prove to be very effective against Tigers (penetration from 1200 meters) and the sloped Panthers (penetration from 600-700 meters). Soviet designers noticed that the blunt-nosed HE ammunition was much more effective against sloped armor. It caused cracking of the armor and could tear off the whole front armor plate at the seam weld. However, in 1944 the problems of the APHE round also disappeared as the German tanks decreased in armor quality due to lack of materials and the Soviet ammunition improved in quality. The IS-2 also improved in quality: from 1944 onwards, the front armor was tempered to a very high hardness, leading to better protection, but higher production costs.
Despite this, the armor protection of the IS-2 was still lower than expected: a Soviet 76.2 mm Gun ZiS-3 could penetrate it from all sides at a distance of 600-700 meters. Not all shots penetrated, but the impacts also caused armor splintering and fragmentation inside the turret. As a result, many many ISs were lost during the winter and spring of 1944. Further modifications meant the German 88mm guns could not penetrate its front armor at point-blank range from an angle of 30 degrees. The turret could not be further modified. The 122mm already caused major imbalances (as the turret was designed for the 85mm gun) and increased armor would result in even more problems. Some smaller improvements to the turret led to an AA-gun and an improved periscope.
Soviet tank doctrine focused on only two tanks, the Medium T-34 tank and successors, and the Heavy IS-2 tank. In total 3,483 IS-2s and 107 IS-1s were produced. Afterward, production shifted to its successors, the IS-3 and IS-4.
The IS-2 tank was designed as a breakthrough tank and proved very effective during the course of the war. The separate breakthrough regiments, previously equipped with KV tanks, could field the new tanks from February 1944 onwards, receiving the "Guards" status in the process. Each regiment of 375 men in total consisted of 21 tanks (4 companies of 5 tanks and a commander tank), an SMG infantry company (riding on the tank), an anti-aircraft battery, a sapper platoon, a medical platoon, and a signal platoon.
The tank crew was, due to formations of new regiments, partly inexperienced. Each tank had four crew members: two lieutenants (the tank commander and the driver) and two sergeants (the loader and the gunner). The big disadvantage of this setup was that the tank commander had a secondary task: operating the radio. This meant that he could not fully concentrate on the battlefield.
The new tanks first saw action on February 15, 1944, during the Korsun-Shevcheskovsk Operation. 5 IS-1 tanks were ordered to help the 109th tank brigade in the assault on Lisyanka village in Ukraine. When the Soviet tanks approached within 600-700 meters, the Germans opened fire and knocked out all Soviet tanks. However, the village was captured the next day.
The first IS versus Tiger battle occurred on the first of March 1944. 1 IS-1 was destroyed and two were crippled after the German Tigers opened fire at a distance of 1500 to 1800 meters. Two Tiger tanks were damaged. More IS-1s were damaged by artillery and field guns and as a result, the Soviet military demanded higher armor quality and the cancellation of the 85mm gun.
The IS-2 was more successful. The 72nd regiment took part in fighting near Oberlin between April 20 and May 10 and destroyed 41 Tiger I and Ferdinand tanks (it should be noted, however, that all German tank destroyers were labeled Ferdinand by the Soviets, most likely the Ferdinands were Stug IIIs in reality). Only 8 IS-2s were lost in the battle.
The Tiger II and the IS-2 only met on a few occasions. Generally, these encounters resulted in high losses on both sides. The first and most successful battle happened between a single IS-2 and 7 King Tigers. The IS-2 ambushed the Tiger IIs and destroyed three of them. The other four retreated.
However, the main task of the IS-2 was not tank versus tank combat. The tank was especially potent against soft targets with its 25 kg HE shells. The appearance of the IS-2 meant the Soviets were now able to break through enemy lines defended by bunkers and AT-guns. At the very end of the war, the IS-2 was successful as a breakthrough tank in the Battle of Berlin, as it was able to destroy buildings with a single shot. At that point in the war, the main enemy of the IS-2 was not the Panther or King Tiger, but infantry with Panzerschrecks or Panzerfausts. 70% of the IS-2s destroyed in that battle were destroyed with these kinds of weapons.
IS-2 After The War
In May 1945, the production of the IS-2 stopped in favor of the new IS-3. However, the IS-2 was used until the 1970s by the Soviet, Chinese, and North Korean army. The last time the IS-2 was used was during the training in 1982, but the vehicle was only definitely scrapped in the 1990s.
During the later stages of the war, the IS series was a primary Soviet tank, mainly used to break through enemy lines. It was the first Soviet tank that was able to face a Tiger or King Tiger one on one. In that role, it did not only have tactical value but also acted as the model for the turn of the war. Soviet morale received a boost after the employment of these tanks.
The IS-2 was on paper a Heavy tank, but it was more mobile and agile than its predecessor, the KV. Internal space was sacrificed for performance and cost-saving.
The IS-2 was the main tank in the final battle on the Soviet front, the Battle of Berlin. It proved to be an excellent fighter in the streets of the German capital.
Armament in turret
Armor (carbon steel)
Power to weight ratio
Maximum speed (km/h)
Total Weight (metric tons)
Roadwheels per side
Number of support points
Track Width (mm)
Track Pitch (mm)
Track Links per side
Track length (m)
Track contact length (m)
Support length (m)
Ground Pressure (kg/cm2)
Ground Clearance (mm)
|IS-1||107||85mm D-5T||59||2,520||60-160mm||4||W-2-IS V-12||600||14.1 hp/t||37||800||150||8-speed||Clutch brake||8.56||3.07||2.73||-||44||6||1-2-2-1||3||-||-||Steel||650||159||87-90||-||4.3||-||0.78||460|
|IS-2||3,483||122mm D-25T||28||2,520||60-160mm||4||W-2-IS V-12||600||11.3 hp/t||37||800||150||8-speed||Clutch brake||8.83||3.07||2.73||-||46||6||1-2-2-1||3||-||-||Steel||650||159||87-90||-||4.3||-||0.8||460|
Historical Accuracy Errata
Like many Soviet tanks in-game, the IS has increased gun depression. In reality, it had -3° with the 100mm and 122mm guns and -5° with the 85mm.
- The 85 mm D5T-85BM gun was only fitted to the SU-85. Its configuration on the IS is fake.
- The IS' engine is considerably more powerful than in reality. with 700 hp compared to the historical 600.
- Historical V-2 IS liquid-cooled V-12 diesel engine with 520 hp is missing.
- Same tank as the Chinese IS-2, yet the engine power values are inconsistent.