Life Steal Information, Math and Speculation

This guide is outdated. With the arrival of M2.0 lifesteal was changed and appears to be affected by all damage boosts a player has. The guide has not been updated to reflect this.

Life steal has become a common place mechanic in the Borderlands series. Borderlands 3 has a few examples of it, Amara and Zane have it baked into their skill trees, Moxxi weapons have returned and there are even anointments that give life steal. As a general rule all life steal works the same in Borderlands 3, there may be an anomaly or two however in all likelihood anything I say here can be applied to any life steal source in the game. I’m only going to speak about healing from your guns damage, I haven’t the time or interest to test Action skills, grenades or other possible life steal sources.

The first thing that may surprise some is that the amount you are healed is not based off your final damage. Just because your fire weapon dealt 100 damage does not mean your 20% life steal will give you 20 health. There are surprisingly few things that affect life steal. Hitting crits, matching elements or adding bonus elemental damage will do nothing for how much you are healed.

There are actually only a few ways to increase healing, to boost Gun Damage, amp your shot or use an anoint with while airborn/sliding. Amp is pretty self explanatory as to what it is, as are the 2 anoints. Gun Damage however needs a bit of explaining, these are the boosts that people casually refer to as additive. I personally hate this terminology and prefer to call them a part of Normal Hit, There are general game wide sources for this buff and there are character specific examples. I’m going to do my best to list every source of these buffs I can, however I am only human so I might forget one. If you don’t see it on the list and think it might belong here please ask.

I’m going to hide each category of buffs, just tap the arrow to expand the list.

Normal Hit Boosts all characters have access to
  • +_% Weapon Damage, this is a passive that can be found on all class mods.
  • +_% Manufacturer Damage, this is a passive that can be found on all class mods.
  • +100% Gun Damage on Actions Skill End anointment.
Amara Specific Normal Hit Boosts
  • Wrath
  • Dread
  • Samsara Gun Damage
  • Jab Cross
  • Spiritual Driver damage bonus for moving.
  • Phasezerker Damage bonus for Rush stacks.
  • +250% Phasecast Anointment
  • +300% Phaseslam Anointment
Fl4k Specific Normal Hit Boosts

Please be aware I have not tested these buffs myself. They follow all rules I have determined on life steal, however as I am not a Fl4k player I have not tested these boosts to confirm.

  • Furious Attack
  • Turn Tail
  • Furryous
  • Persistence Hunter
  • Dangerous Game
  • Grim Harvest
  • Horned Skag Gun Damage Bonus
  • Stackbot
Moze Specific Normal Hit Boosts
  • Armored Infantry
  • Drowning in Brass
  • Desperate Measures
  • Phalanx Doctrine
  • Tenacious Defense
  • Click, Click…
Zane Specific Normal Hit Boosts
  • Confident Competence
  • Violent Momentum
  • Donnybrook
  • Synchronicity
  • Double Barrel
  • Retaliation
  • Infiltrator Class Mod
  • Antifreeze Mod
  • +130% damage on Clone Swap anointment

Life Steal Formula

Life steal is calculated as:

Health Returned = Life Steal % x Normal Hit x Amp x Airborne/Slide

  • Normal Hit = Gun Card Damage x [ 1 + Normal Hit Boost ]
    Where Gun Card Damage is the damage listed on the guns item card. If you have multiple normal hit boosts you add them all together and then sub them in for Normal Hit Boost
  • Amp sources all multiply each other. So if you fire an amped Redistributor shot through a grounded Zane’s Barrier you’ll have amp = 1.5 x 1.25 = 1.875
  • The slide and airborne anoints can never both be active at once so we don’t know their interaction. However both are fully multiplicative to the rest of the life steal formula.


For awhile now I’ve known of a few of these damage sources that affect life steal but I’ve not been quite sure what the link is. I’ve been speculating on what it is and had a few of my ideas shot down through testing. I suspect the following idea could also prove to be false, but I’ll present it anyway as my current guess.

The Borderlands damage formula is calculated in stages, some of it is calculated when you fire your gun. Examples of this are things like Zane’s Violent Momentum, which takes his speed when the shot is fired. There are multipliers applied while the bullet is in flight, like Zane’s barrier amp. Then lastly there are a host of modifiers that are applied when the bullet impacts the enemy, things like the elemental damage bonus and whether or not the shot was a critical hit.

From my testing almost all damage bonuses are calculated once the bullet hits the enemy. Boosts such as splash damage and specific weapon type boosts are calculated here. The only boosts that do not seem to get calculated on impact are Normal Hit, Airborne/Slide anoints and Amp damage. If it didn’t click immediately, then notice now that these are the same boosts that affect life steal.

My hypothesis is that when a bullet impacts a target, 2 processes start. The first is the life steal calculation which takes the prescribed percentage from the damage calculated for the bullet on impact. This is then returned as health. The second process is the actual damage calculation that adds in modifiers such as splash, critical hits and weapon type boosts.

If my hypothesis is correct then any damage that is calculated before impact will affect life steal. This holds for weapons that charge, the bonus charge damage does directly affect how much you are healed. As does the Dahl semi auto bonus on their Assualt Rifles.

Other Interesting Life steal Resources


A massive thank you to everyone who has assisted in the compilation of the VH Formulas doc. This doc is managed by SSpyR#7851 on discord. The information within has been vital in my ability to test life steal on different characters.


Interesting. Most of FL4K’s Normal hit (additive, whichever, adjusting to new terminology is a pain) is in the Stalker tree, which also has most of their health regen.

Stalker: 70%
Master: 42%
Hunter: 68%

So using your previous example: if you are dealing 100 damage, have 20% lifesteal, and are specced into Furious Attack, Turn Tail, and Furryous, would the final heal value be ((100 * (1+.2+.25+.25)) * .20 = 34?


If your guns card says 100 then yes.

For the sake of clarity: additive damage = normal hit = base damage right?
I am personally used to the terminology “base damage” meaning it’s the number listed on the card

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Normal Hit is what people sometimes call additive damage and includes all the gun damage boosts I list in the thread.

The damage listed on the card I labeled Gun Card Damage. I do occasionally call this base damage but I know people refer to Base Damage as quite a few things so I wanted to avoid using it.