Health vs resistances in LoL: when to buy which
The question “do I buy health or resistances?” has an exact answer, not a gut one. Because health and resistances multiply in your effective HP, stacking only one is rarely best: the trick is balancing them against the damage you face. This guide gives you the formula and how to decide with the site’s tools.
The effective-HP formula: why they multiply
Effective HP (EHP) measures how much raw damage of one type you survive before dying. Against a single damage type the formula is simple: EHP = health × (1 + R/100), where R is your armor (against physical damage) or your magic resist (against magic damage). With 2000 health and 100 armor, your physical EHP is 2000 × 2 = 4000.
The key point is that health and resistance multiply, they don’t add. That’s why buying armor pays off more the more health you already have, and buying health pays off more the more resistance you have. Stacking one stat has diminishing returns in real survivability; balancing both makes every purchase worth more.
Beware a common misconception: the mitigation percentage does have diminishing returns (from 100 to 200 armor you go from 50% to 67% reduction), but effective HP does not. Each 100 armor adds exactly “another copy of your base health” in EHP. The intuition that “armor does less the more I have” is false if you look at survivability, not the percentage.
You can input your health, armor and MR in the mitigation Lab to see your EHP against physical, magic and mixed damage, and instantly check how much each purchase raises your survivability.
EHP = vida × (1 + R / 100) | Armor | Reduction | Damage from 1000 | EHP with 2000 HP |
|---|---|---|---|
| 0 | 0% | 1000 | 2000 |
| 25 | 20% | 800 | 2500 |
| 50 | 33.3% | 667 | 3000 |
| 100 | 50% | 500 | 4000 |
| 150 | 60% | 400 | 5000 |
| 200 | 66.7% | 333 | 6000 |
| 300 | 75% | 250 | 8000 |
The mitigation engine with the real formula: damage taken = damage × 100 / (100 + armor).
The “armor ≈ health + 100” balance
There’s a very useful mental rule for knowing what to buy next. Since EHP is the product health × (1 + R/100), you should spend your next unit of gold on whichever is “lower” relative to the other. The balance idea is summed up as “effective armor ≈ health + 100” (and the same with MR).
In practice this means: if your armor (plus 100) is below your health, the next armor purchase gives more EHP per unit than more health; if it exceeds it, buy health. The “+100” comes from the formula 1 + R/100 itself, which is what multiplies your health.
It’s not a magic number you must hit exactly: it’s a compass. It tells you which way to tilt the build, not to ignore context. An item that mixes health with armor usually moves you toward the balance better than a pure-health or pure-resistance item, because it pushes both factors at once.
To avoid eyeballing it, the mitigation Lab shows the exact EHP with your current stats, and the compare tool lets you put two defense profiles side by side and see which survives more against a given damage. That swaps intuition for current-patch numbers.
The % reduction flattens (diminishing returns), but effective HP rises in a straight line: every point of armor adds the same EHP. That’s why armor never "gives less" for survivability.
Counters: what melts pure health and what melts pure resistance
Balance isn’t only efficiency: each extreme has a counter. Pure health melts against two things: percent penetration and damage that scales with the target’s max health. If an enemy takes a % of your health per hit, having more health doesn’t save you proportionally: it hits harder the more health you carry.
Pure resistance melts against true damage, which completely ignores armor and MR. Against a champion with lots of true damage, stacking resistances does almost nothing and raw health is the only thing that helps you survive. Flat penetration also cuts resistance value, but never takes it below 0.
Hence the practical rule: health protects you against true damage and flat burst; resistances protect you against repeated normal damage and mitigable physical/magic. Neither covers everything alone, which is why the balanced mix is so robust: it closes both flanks at once.
Before locking your build, think about the enemy’s penetration type. Lots of percent penetration punishes those who stack resistance; lots of true or %-health damage punishes those who stack health. Checking the mitigation Lab with the enemy penetration enabled shows your real EHP, not the whiteboard one.
From 1000 raw damage of each type into a target with 100 armor and 60 MR. True damage ignores resistances: all 1000 land. That’s why it’s so valuable against tanks.
Mixed vs single threats: how to decide with the tools
When the enemy has a single dominant damage type, the call is straightforward: buy the resistance that mitigates it (armor against physical, MR against magic) until you approach the balance with your health, then balance from there. There’s no point buying the resistance the enemy doesn’t use.
Against a mixed comp (physical and magic damage spread out), it changes: there health is usually the best buy, because it protects against both types at once. A resistance only covers half the damage you take; health multiplies your EHP against everything, so it pays off more when you can’t know which side the hit comes from.
The honest way to decide isn’t from memory but with patch numbers. Build your defense in build, face it against the enemy damage and see if you survive the combo; use compare to put two item paths side by side (for example “more health” versus “more armor”) and see which gives more EHP against that specific comp.
The summary is simple: single damage type → the right resistance; mixed damage → health; in both cases, balance toward “armor ≈ health + 100”. Don’t invent exact item numbers: let the mitigation Lab, build and compare use the real patch values and decide with data.
FAQ
Is it better to buy health or resistances?
It depends on which one you’re more unbalanced in and on the enemy damage. Since health and resistances multiply in effective HP (EHP = health × (1 + R/100)), buy whichever is lower to approach the “armor ≈ health + 100” balance. Against a single damage type, the right resistance; against mixed damage, health. Check your exact EHP in the mitigation Lab.
Why doesn’t armor have diminishing returns?
Because effective HP grows linearly with armor: each 100 armor adds “another copy of your base health” in EHP. What does have diminishing returns is the mitigation percentage, but that percentage isn’t what measures your survivability. Confirm it by entering different values in the mitigation Lab: EHP rises evenly.
How do I protect against true damage and percent damage?
Against true damage, resistances don’t help: only more raw health (or shields and healing) does. Against percent penetration and %-max-health damage, stacking pure health does little; there you should mix health with resistance or cut the damage another way. The key is not going to an extreme: the balanced build covers both counters at once. Check it in compare.