All enemies encountered in WARFRAME have a certain level, which determines their strength by increasing some of their base statistics. The stats amplified by enemy level gain are Health, Armor, Shields, Damage dealt, and Affinity on death. The purpose of this article is to show how exactly these stats scale with level, how this translates to useful indicators such as effective health, and what implications this has towards player decision making such as Aura mods or damage type selection.
Note that enemy levels can only reach to a maximum of level 10000 with some edge cases (e.g. Eximus spawns).
Common Features of Stat Scaling[]
How scaling of fundamental enemy stats works in general is identical for all the stats: Each enemy type has a base value for this fundamental stat and a base level, the current value of the stat at the current level of the enemy is then calculated after a formula of the following structure:
Exponent and coefficient are determined by the specific stat in question but are equal across all enemy types. The base level and base value of the stat are determined by the enemy type. The current level is then the independent variable and the current value of the stat is the dependent variable of the formula.
At lower levels the coefficient is normally less than one, so growth is not easily noticed until midlevel ranges. For high levels, the exponent has the most impact when comparing different scaling stats against each other. If the exponent is 1, the scaling of the stat would be linear with level, which means the increase in value as level grows would be constant. For exponents higher than 1, each successive levelup grants a larger increase than the previous one, and for exponents lower than one, each successive levelup grants a smaller increase than the previous one.
The only exception of this common structure is Affinity scaling, where the current level is used instead of the difference between the current and base level.
Scaling of Fundamental Stats[]
As mentioned, all fundamental stats scale by the above formula structure and common features apply. A standardized graph is shown for each stat. When comparing the graphs, the different Yaxis scaling has to be considered. As of Update 27.2 (20200305) health, shield, and armor scaling follow an "S"like curve, where below a universal level range these stats grow "exponentially", and above this range, the stats grow slower and begin to plateau.
Health, shields, and armor scaling formulae use two main functions to determine stat scaling at a particular level. One function is used when enemy level difference is below 70 and the other when enemy level difference is above 80. A common feature between the functions used is that they intersect at x=80. In other words, they produce the same value when the enemy level difference is 80.
Stat scaling between 7080 inclusive is interpolated from the two functions using smoothstep.

 Finding out transition percentage from 70 to 80

 Smoothstep transitioning between functions
Note that while the growth at early levels is normally referred to as exponential by the community, it is actually a power growth of the form x^{n}, which is an order less than exponential growth (i.e. x^{n} ∈ O(n^{x}) v. n^{x} ∉ O(x^{n})). For simplicity's sake however, it will still be referred to as exponential growth throughout the article.
Note that the following health, shield, and armor scaling formulae are derived from ingame testing and have not been confirmed or denied valid by Digital Extremes at this time. The accuracy of the following information is still under review.
Health[]
For health, the ranges of level differences from base to current level at which scaling transitions from exponential growth to a plateau is between 70 & 80. The formula by which enemy health scales is as follows:
 (Original scaling preUpdate 27.2 (20200305))
 When Current Level  Base Level < 70

 When Current Level  Base Level > 80

 Where the Health Multiplier is the value that multiplies an enemy's base health to its current health.
Shields[]
For shields, the ranges of level differences at which scaling transitions from exponential growth to a plateau is between 70 & 80. The formula by which enemy shields scale is as follows:
 (Original scaling preUpdate 27.2 (20200305))

 When Current Level  Base Level < 70

 When Current Level  Base Level > 80

 Where the Shield Multiplier is the value that multiplies an enemy's base shields to its current shields.
Armor[]
For armor, the ranges of level differences at which scaling transitions from exponential growth to a plateau is between 70 & 80. The formula by which enemy armor scales is as follows:
 (Original scaling preUpdate 27.2 (20200305))
 When Current Level  Base Level < 70

 When Current Level  Base Level > 80

 Where the Armor Multiplier is the value that multiplies an enemy's base armor to its current armor.
Damage[]
The formula by which enemy damage scales is as follows:
Affinity[]
The formula by which enemy affinity scales is as follows:
Note that this is a special case: for the affinity scaling, base level is not subtracted from the current level. The base affinity multiplied by the Affinity Multiplier value is also rounded down to a whole number, e.g. 62.7 affinity will be rounded down to 62.
Scaling of Fundamental Stats (Eximus)[]
As of Update 31.5 (20220427), Eximus units follow different scaling formulas for their fundamental stats.
Health, shields, and armor scaling formulae use six different functions to determine stat scaling at a particular level:
 When enemy level difference is below 26
 When enemy level difference is between 26 and 35 inclusive
 When enemy level difference is between 36 and 50 inclusive
 When enemy level difference is between 51 and 70 inclusive
 When enemy level difference is between 80 and 100 inclusive
 When enemy level difference is over 100
Stat scaling between 7080 inclusive is interpolated from the two functions using smoothstep.

 Finding out transition percentage from 70 to 80

 Smoothstep transitioning between functions
Note that the following health, shield, and armor scaling formulae are derived from ingame testing and have not been confirmed or denied valid by Digital Extremes at this time. The accuracy of the following information is still under review.
Health[]
For Eximus enemies with health (e.g. Charger or Corrupted Lancer), the same curves are used for scaling with smoothstep interpolation between level difference 70 and 80, but the base health is increased between certain breakpoints:
 Between level differences 0 inclusive and 25 inclusive, base health stays the same as listed in the Codex.
 Between level differences 25 exclusive and 35 inclusive, base health is linearly increased from +0% to +50% (e.g. for each level, enemy gains 5% base health).
 Between level differences 35 exclusive and 50 inclusive, base health is linearly increased from +50% to +200% (e.g. for each level, enemy gains 10% base health).
 Between level differences 50 exclusive and 100 inclusive, base health is linearly increased from +200% to +300% (e.g. for each level, enemy gains 2% base health).
 Above level difference of 100, base health will stay +300% (4x) of its Codex value.
 (Original scaling preUpdate 27.2 (20200305))
 When Current Level  Base Level < 70

 When Current Level  Base Level > 80
Shields[]
For Eximus enemies with shields (e.g. Corpus Tech or Shield Osprey), the same curves are used for scaling with smoothstep interpolation between level difference 70 and 80, but the base shields is increased between certain breakpoints:
 Between level differences 0 inclusive and 25 inclusive, base shields stays the same as listed in the Codex.
 Between level differences 25 exclusive and 35 inclusive, base shields is linearly increased from +0% to +32.5% (e.g. for each level, enemy gains 3.25% base shields).
 Between level differences 35 exclusive and 50 inclusive, base shields is linearly increased from +32.5% to +130% (e.g. for each level, enemy gains 6.5% base shields).
 Between level differences 50 exclusive and 100 inclusive, base shields is linearly increased from +130% to +195% (e.g. for each level, enemy gains 1.3% base shields).
 Above level difference of 100, base shields will stay +195% (2.95x) of its Codex value.

 When Current Level  Base Level < 70

 When Current Level  Base Level > 80
Armor[]
For Eximus enemies with armor (e.g. Heavy Gunner or Lancer), the same curves are used for scaling with smoothstep interpolation between level difference 70 and 80, but the base armor is increased between certain breakpoints:
 Between level differences 0 inclusive and 25 inclusive, base armor stays the same as listed in the Codex.
 Between level differences 25 exclusive and 35 inclusive, base armor is linearly increased from +0% to +12.5% (e.g. for each level, enemy gains 1.25% base armor).
 Between level differences 35 exclusive and 50 inclusive, base armor is linearly increased from +12.5% to +37.5% (e.g. for each level, enemy gains 2.5% base armor).
 Between level differences 50 exclusive and 100 inclusive, base armor is linearly increased from +37.5% to +62.5% (e.g. for each level, enemy gains 0.5% base armor).
 Above level difference of 100, base armor will stay +62.5% (1.625x) of its Codex value.
 (Original scaling preUpdate 27.2 (20200305))
 When Current Level  Base Level < 70

 When Current Level  Base Level > 80
Overguard[]
Overguard is a unique health buffer to Eximus, though normal units can get overguard in unique sitations (like after a Overguard Exodamper is destroyed during Void Armageddon).^{[1]}

 When Current Level  Base Level < 45

 When Current Level  Base Level > 50
Stat scaling between 4550 inclusive is interpolated from the two functions using smoothstep.

 Finding out transition percentage from 45 to 50

 Smoothstep transitioning between functions

 Where the Overguard Multiplier is the value that multiplies an enemy's base overguard to its current overguard.
Damage[]
The formula by which enemy damage scales is as follows:
Affinity[]
The formula by which enemy affinity scales is as follows:
Note that this is a special case: for the affinity scaling, base level is not subtracted from the current level. The base affinity multiplied by the Affinity Multiplier value is also rounded down to a whole number, e.g. 62.7 affinity will be rounded down to 62.
Scaling of Derived Stats[]
From these fundamental stats, more meaningful stats can be derived.
Effective Hitpoints[]
Effective Hitpoints is a stat that indicates how much gross damage must be dealt to a target until the net damage thereby inflicted depletes its entire health pool. Effective Hitpoints is not a fixed stat for any given enemy, it is heavily dependent on the damage type used against the target, as well as the various buffs and debuffs in effect for both the attacker and the enemy in question. For the following considerations, however, these influences are disregarded, as they do not alter the course of the graphs except for clinching or stretching them as a whole, which manifests as a scaling of the Yaxis.
For Enemies with Health only[]
For targets without shields and armor, the standardized effective hitpoint scaling is synonymous with standardized health scaling, the health graph and formula apply.
For Enemies with Health and Shields[]
The standardized effective hitpoints of shielded enemies are simply the sum of their shields and health, except for the case when the Toxin damage portion of the gross damage depletes the target's health faster than the rest of the gross damage depletes its shield. Exact effective hitpoint calculations considering damage types also become significantly more complex if Toxin damage is involved, but this is disregarded here. The level scaling of standardized effective hitpoints of shielded enemies is influenced by the ratio of base shields to base health:
In the cases where you are trying to oneshot shielded enemies without Toxin damage, their effective hitpoints will actually be higher due to their shield gate mechanic. Only 5% of total damage dealt will only damage the enemy's health when their shield gate is active. However, attacking enemy weakpoints ignores the shield gate.
For Enemies with Health and Armor[]
The standardized effective hitpoints of armored enemies are simply the health divided by the compliment of the damage reduction granted from armor. Because armor adds damage reduction to incoming damage on health the level scaling of standardized effective hitpoints of armored enemies is influenced by the base armor itself:
For Enemies with Health, Shields, and Armor[]
The standardized effective hitpoints of enemies that are both armored and shielded are more complex than the simple EHP cases from the previous sections above. The level scaling of standardized effective hitpoints of these enemies is influenced by the ratio of base shields to base health and base armor, making the formula at least 3 variable:
Shielding Ratio[]
The shielding ratio of shielded, unarmored enemies is the ratio of their shield to their health. Since health and shield scale at different rates, this ratio changes with level. PreUpdate 27.2 (20200305) this ratio used to converge towards a 1:2 ratio, where the higher the level the enemies, the closer they were to having twice as much health as shields, regardless of base stats. Currently, the ratio follows this original trend up until level 70, where it suddenly dips below 1:2 then diverges off towards infinity. This is because unlike before when health and shield scaling had same exponents (2), the current shield scaling has an exponent 50% larger than health scaling (0.75 vs 0.5) once past level 80, so it will grow at a faster rate despite having a smaller coefficient. This means the shield ratio will also grow larger over levels rather than converging.
The shielding ratio is relevant for evaluating and selecting damage types against shielded enemies, i.e. weighing benefits against shield types against benefits against health types. Eventually shielded enemies at high enough levels will have more shields than health, so assuming a lack of Toxin or True damage, effectiveness against shields may take more precedence in player builds than health effectiveness.
The shielding ratio of shielded, armored enemies is the ratio of their shield to their armored EHP. Like before, since health and shield scale at different rates, this ratio changes with level, though more complexly since armor scaling will also make an impact. This ratio converges towards a 0:1 ratio, where, as long as the enemy has a base armor of at least one, the higher the level the enemies the closer they are to having a negligible amount of shields relative to their EHP due to armor. Though as seen above, if no armor is present then the ratio will diverge towards infinity.
Affinity Density[]
The affinity density of an enemy is its affinity per effective hitpoints and a measure of its profitability for affinity farming.
It is important to note the actual affinity farming profitability is significantly offset off the optimal area as implied by the affinity density function due to the two important practical influences of overkill and retargeting time, which both contribute to shifting the actual optimum from these implications towards higher levels.
Reflective Kill Rate[]
Reflective kill rate of an enemy is the ratio of its damage output and effective hitpoints. This is inversely proportional to the amount of time or attacks an enemy would need to kill another of its kind. It's a measurement for the effectiveness of damage reflecting effects and abilities, such as the Radiation damage proc, the Reflection mod, and abilities such as Link, Shadows Of The Dead, Absorb, Chaos or Mind Control.
Level Scaling During Endless Gameplay[]
During endless missions such as Survival, Defense, and Disruption, enemy spawn level will increase exponentially the more reward rotations are completed. Typically at around 8+ hours of inmission time, players will reach the max enemy spawn level.
In Disruption missions, to calculate the approximate spawn level at a particular conduit number^{[2]}:
External Links[]
Interactive calculator for most value multipliers^{[3]}
References[]
 ↑ chrookee (2022, May 2). [Confirmation needed]I did a little math on the Overguard, here is the result. Reddit. Accessed 20220503. Archived from the original on 20220503.
 ↑ Spreadsheet by PGSSJ.OneeChan
 ↑ by User:Gigamicro
Patch History[]
Update 27.2 (20200305)
 Armor and Damage Changes (Enemy):
This section will go over before and after scenarios with our enemy Armor, Health, and Shield changes. Reading this section should give you a conceptual and onpaper understanding of what we’re changing and why, but practical experiences will tell the full story here. You may need to refresh some aspects of your Builds to truly optimize your power against your enemies.
Before: Armor, Shields and Health on an Exponential Curve
After: Armor Shields and Health on an S curve
 Damage Changes:
Enemy Damage output should still be close to what is currently on the Live version of the game, but we have made a few changes that will affect how players take Damage ingame.
 Infested Damage:
We did not want to overlook the Infested in our review. Infested are closerange enemies that telegraph most attacks  and now if one of those attacks hits you, it simply does more damage. Stay agile, stay moving, and the mission is as good as won!
Why: Having Infested simply deal more Damage encourages you to use mobility in ways that is not the norm for their ranged counterparts. Rewarding mobility is a key part of Warframe.
 AI Aimbots
Up until now in Warframe, the higher the enemy level, the better their accuracy. Highlevel enemies would be pinned at the best Accuracy they are capable of  not quite 100%, but getting pretty close! Things like your movement and Mods would reduce accuracy, but the potential for bad ‘Aimbot’ moments was too high. We have spread this progression across a greater range of AI now We are decoupling enemy accuracy from level to reduce the overall ‘Aimbot’ like behaviours you face at higher levels.
Why: This change allows us more accurate balancing of foes at higher levels. This change alone would be noticed by simply sometimes ‘getting hit less’, but in conjunction with the numerous other changes we are making to enemies, it is part of a holistic Refresh to the underlying mechanics behind Warframe’s enemies.
Hotfix 25.0.7 (20190530)
 Eximus enemies are now capped at Level 9999 like regular enemies.
Update 14.0 (20140718)
 Enemies health is no longer capped at 65535.
Update 11.5 (20131219)
 Armour/Shield/Health/Damage curves have been modified. We’ve lowered the “bullet sponge” to high level enemies, but they now deal more damage. The armour curve was radically dropped. The health and shields curves dropped slightly as well. However, damage output went up.
Update 11.0 (20131120) Source: https://forums.warframe.com/topic/132366informationondamage20/
 Enemy Levels
Enemy levels now fall in a more compressed scale. Level 1 enemies are still the easiest, but the difficulty of a Level 40 enemy in Damage 2.0 will be comparable to a Level 100 enemy in Damage 1.0. Infinite mission types will still feature ever increasing enemy levels. Enemies will be wielding weapons that can inflict different types of damage and Procs on the Tenno, meaning the difficulty will come from a combination of their loadouts and their level.