What the number measures
Time to kill, often shortened to TTK, is how long it takes one player to eliminate another once shooting begins. It depends on the target’s health, the damage per shot, how many shots are needed, and how quickly the weapon fires. It is one of the most important numbers in a shooter because it governs how fights feel: whether you can recover from being surprised, whether the player who shoots first almost always wins, and how much accuracy matters compared with positioning.
A short calculation
A common convention is to count from the first shot landing to the last, so the time depends on the gaps between shots rather than the number of shots.
Suppose a target has 100 health and a weapon deals 25 damage per hit. It takes 4 hits. There are 3 gaps between 4 shots. If the weapon fires 600 rounds per minute, that is 10 per second, so each gap is 0.1 seconds. The TTK is 3 × 0.1 = 0.3 seconds, assuming every shot hits.
Now change the damage to 20. It takes 5 hits, so 4 gaps: 4 × 0.1 = 0.4 seconds. A small change in damage per shot raised the time by a third, from 0.3 to 0.4 seconds. These numbers are invented for illustration, and real games add armour, range falloff, headshot multipliers and other details, but the structure is the same.
Fast time to kill
When eliminations take a fraction of a second, the first player to land hits tends to win. Fights are short and unforgiving. This has several consequences:
- Positioning dominates. Being in the right place with the crosshair already aimed matters more than reacting after the enemy appears.
- Reaction is limited by human speed. Because reaction time has a floor, no player can consistently respond to being shot at in the span of a very short fight. Prediction and pre-aiming take its place.
- Information is valuable. A sound or a glimpse that reveals an enemy can decide the encounter before it starts.
- Mistakes are costly. There is little time to correct a poor angle.
Games with fast TTK tend to produce tense, methodical play with frequent peeking and holding of angles.
Slow time to kill
When eliminations take longer, fights allow for back-and-forth. A player who is shot first can still turn the fight by using cover, abilities or a teammate’s help. This favours:
- Tracking and consistent aim, since the fight lasts long enough for aim quality to accumulate.
- Ability use and team play, because there is time for abilities and teammates to affect the outcome.
- Recovery, since being out-positioned is not always a death sentence.
Slow TTK games often reward sustained fights and give weaker players more opportunity to survive, though they can feel less decisive for skilled players.
Weapon roles
Designers rarely want every weapon to have the same TTK at every range. Instead, weapons are tuned to be best in particular situations, which gives them roles.
A close-range weapon might have a very short TTK up close and a long one beyond a few steps. A long-range precision weapon might kill in one or two hits but fire slowly and punish misses. A general-purpose rifle might sit in the middle at most ranges. The aim is that choosing a weapon is a choice about what you expect to face, and that each has a counter. This is a case of counterplay design: a weapon that excels at one range should be vulnerable at another.
Range falloff, where damage drops with distance, is a common way to shape these roles. Fire-rate and recoil add further limits. A weapon with a theoretically excellent TTK can still be weak if it is hard to keep on target.
Variance in the damage
TTK is usually quoted for ideal conditions. In real play, hit locations vary, shots miss, and some games add critical hits or random spread. Randomness in the number of shots needed means the same weapon can have a short or longer real TTK in different fights. Designers must decide how much of this variation to allow. More variance means upsets are more common and skill gaps appear smaller, whereas low variance makes outcomes more consistent.
Balance and change over time
Weapon balance is checked using usage and performance data. If a weapon is picked far more than others and wins more, it may be too strong. If it is rarely picked, it may be too weak or may simply be hard to use. Data can be misleading, though: a weapon may have a high win rate because experienced players prefer it, not because it is inherently better. Adjusting damage, fire rate or range falloff is a common type of balance patch, and even small changes can have large effects because TTK depends on whole-number shot counts. For example, dropping damage from 25 to 24 in the earlier example changes the required hits from 4 to 5, since 4 × 24 = 96 is less than 100.
That last point is one reason designers like to check damage values against typical health totals: crossing a threshold changes the number of shots needed, and the TTK jumps rather than shifting smoothly. It is similar in spirit to the way frame data in fighting games turns small timing differences into large practical ones.