Build Calculator Guide

The Build Calculator adds up the stats of a loadout you assemble by hand: armor, container, artifacts, buffs and grenades. From the totals it calculates four summary values: EHP, healing, combined speed and effective stability. Nothing is searched or simulated; each value is a direct calculation, and each stat lists the items it comes from. This guide explains those calculations and their limits.

Building a loadout

• •Choose an Armor System and its level, then a Container. The container sets the number of artifact slots, its effectiveness and its inner protection.
• •Fill the slots. For each artifact set its Rarity, Level and active Additional Stats.
• •Add Buffs & Consumables and Grenades if you want them counted.
• •Read Final Stats. Harmful accumulation above its limit is highlighted.

How artifact stats are scaled

• •beneficial stat = maximum value × (rarity ÷ 100) × (1 + 0.3 × level ÷ 15) × container effectiveness
• •Rarity and level both scale beneficial stats linearly. Each level adds 2% of the value, so +15 gives +30%.
• •Downsides are not scaled by level or container effectiveness. Within each rarity tier (starting at 101, 116, 131, 146, 161%) a downside rises from its smallest value at the first roll of the tier to its largest at the top, then starts low again in the next tier. The rarity presets sit at the top of their tier.
• •One additional stat becomes active every 5 levels, up to 3 at +15.

Inner protection and infection limits

When your artifacts' combined radiation, thermal, biological or psy accumulation is positive, the container removes its inner-protection percentage of it:

• •accumulation after inner protection = artifacts' accumulation × (1 − inner protection ÷ 100)
• •Example: with 50% inner protection, artifacts that together add +4 radiation contribute +2.
• •Frost accumulation is not reduced.
• •The limit is 10 for each of the four, and 0 for frost. The reduction appears as its own line in the stat's sources. Values are in the game's units. The frost total includes the natural removal of -20, so the items can add up to 20, the frost threshold the game shows on containers.

Effective HP (EHP)

• •EHP = 100 × (1 + bullet resistance ÷ 100) × (1 + vitality ÷ 100)
• •Written another way: (100 + bullet resistance) × (100 + vitality) ÷ 100.
• •Example: 100 bullet resistance and 10% vitality give 100 × 2 × 1.1 = 220 EHP.

EHP is the amount of bullet damage, before armor penetration, that the build can take. It is the calculator's survivability model, not an official game value. It does not include other protections, armor penetration, plates or other damage types; use the TTK Calculator to test a build against a specific weapon.

Healing

Potential Healing adds up the healing stats without status effects:

• •periodic healing × (1 + healing effectiveness ÷ 100) + (2.5 + regeneration) × 20%
• •Periodic healing is the healing stat from artifacts and buffs. Healing effectiveness multiplies only periodic healing.
• •Regeneration starts from a base of 2.5 and counts at 20%, because the calculator assumes you are in combat. Healing effectiveness does not affect it.

Actual Healing (the Healing value) is Potential Healing after the effects your own build causes over the Buildup Duration. Burning lowers healing effectiveness and regeneration and drains health. Bleeding, toxic and frost levels lower healing effectiveness and regeneration. Grenade damage over time is subtracted. Health lost to bleeding, toxic or frost is not subtracted.

Flat HP/s = Actual Healing × EHP ÷ 100. It expresses healing in the same units as EHP, so the same healing percentage is worth more on a tankier build.

Speed and stability

• •Combined Speed is movement speed + sprint speed. No cap, weight penalty or frost slowdown is applied.
• •Effective Stability combines laceration protection and stability: (1 − 100 ÷ (100 + laceration protection) × (1 − stability ÷ 100)) × 100, with stability capped at 100.

Best Upgrade

Best Upgrade answers one question: which single artifact gains the most from one rarity step?

• •It tries each filled slot on its own, raising that artifact to the top of the next rarity tier. Artifacts already in the highest tier are skipped.
• •Level and additional stats stay the same. Only rarity changes.
• •For each try it recalculates the whole build and compares one value: EHP, Actual Healing or Combined Speed, depending on the button.
• •It highlights the slot with the largest increase. If no slot improves the value, it says so.

It does not check infection limits. Raising a rarity puts the artifact's downsides at the top of the new tier, so check the accumulation after an upgrade.

Saving and sharing

Signed in with an EXBO account, you can save up to 20 builds to your account. A share link or an exported image needs no account.

What the calculator does not model

• •No weapons, plates or incoming damage.
• •Only bullet resistance scales with armor level.
• •Status effects come only from the build's own accumulation, not from enemies.
• •Healing items used during a fight are not modelled; only healing stats count.
• •Values come from the site's current game data. If an update changes an item in a saved build, the calculator recalculates it and shows a warning.