How to Theorycraft a Build

Build maths has a recurring shape. The obvious way to combine two numbers — add them, compare them directly, take the bigger one — gives an answer that is not just imprecise but wrong in a consistent direction, and the error grows exactly where the stakes are highest.

These five tools cover the places that happens. None of them needs your game's internals; they work on numbers you can read off your own character sheet.

Start with damage per second, not damage per hit

The number on your weapon is a per-hit figure, and per-hit figures cannot be compared between weapons that attack at different speeds.

The DPS Calculator folds attack speed, crit chance and crit damage into one figure. Its useful trick is showing the Average hit alongside it: at 250 base damage with a 25% crit chance and a 2× multiplier, your average hit is 312.5, not 250 — and 20% of your total damage is coming from crits.

That share matters for more than curiosity. A build drawing a fifth of its damage from crits is much streakier than one drawing none, and Time to kill the target is an average that a bad run of luck will not respect.

Then work out which stat to buy next

Once you know your damage, the question becomes what to spend the next point on — and for crit builds the answer flips depending on where you already are.

The Crit Chance vs Crit Damage Calculator settles it. At 25% chance and a 150% crit damage bonus, one point of crit chance is worth three times what a point of crit damage is worth.

It also gives you the flip point, which is the genuinely useful output: those two stats balance at a crit damage bonus of 50, or equivalently at 75% crit chance. Below the balance point, buy crit damage; above it, buy crit chance.

The intuition people arrive with is usually backwards. Very high crit damage makes crit chance the better buy, not crit damage — because a crit that hits enormously hard is worth making happen more often.

Resistances multiply — they never add

This is the single most common defensive mistake, and the error runs one way.

The Damage Reduction Stacking Calculator does the arithmetic properly. Sources of 30%, 20% and 15% do not give you 65%. They give you 52.4%, because each one applies to what is left after the last. The naive sum overstates your protection by 12.6 percentage points.

Two consequences worth carrying:

• You can never reach 100% by stacking percentage reductions. Each source only ever takes a bite out of the remainder.
• The overstatement is worst when you have the most sources, which is to say at exactly the point in a build where people feel safest.

Judge defence in effective health, not in percentages

A percentage of damage reduction is impossible to compare against a lump of health, which is why gearing decisions between the two feel like guesswork.

The Effective Health Calculator converts everything to one currency. 5,000 health at 40% reduction is 8,333 effective health — your health bar goes 1.67 times further.

Its most important output is Ten more points of reduction would add, because it exposes how sharply resistance accelerates. The same ten points, on the same 5,000 health bar:

Reduction you already have	Ten more points adds
0%	556
40%	1,667
80%	25,000

Identical ten points, fifteen times the value at 80% that it has at 40%, and forty-five times what it is worth at the start. Nearly all of a resistance bar's value lives in its last stretch — which is why capped resistance is worth so much more than it looks, and why chasing your first 10% is close to pointless.

This also explains something the reduction calculator hints at: a source that adds only 4.76 points of real reduction can still multiply your effective health by 1.111. Small numbers on the percentage scale are large numbers on the survival scale.

Then check the upgrade is worth its price

Knowing which stat you want is a different question from knowing which item to buy, because items have prices.

The Gear Upgrade Cost Efficiency Calculator scores any upgrade as cost per 1% gained, which puts a cheap trinket and an expensive weapon on the same scale. It also converts the price into hours of earning, which is the currency you are really spending.

The result worth knowing: which of two upgrades wins does not depend on how strong you are. Both percentages measure against the same character, so your base divides out of the comparison entirely. A ranking never needs redoing because you levelled.

The short version

1. Compare weapons on DPS, never on the number printed on the weapon.
2. High crit damage makes crit chance the better buy — check the balance point, not your gut.
3. Reductions multiply. 30 + 20 + 15 is 52.4%, not 65%, and you can never reach 100%.
4. Convert defence to effective health before comparing it to anything.
5. Score upgrades as cost per 1%, and remember that the winner is the same at every power level.

Every one of these has a printable sheet. The reduction and effective-health ones are worth having side by side, because they answer the same question from opposite ends.