How are expected attempts per level calculated?

For an independent attempt with success probability p, the expected number of tries to one success is 1 divided by p. A 25% chance averages four attempts per level, and the cost scales with that.

What is the difference between reset and hold on failure?

With hold-on-failure, each level is independent and total expected attempts is just the per-level expectation times the number of levels. With reset-on-failure, a failure sends you back to the start, so expected attempts grow much faster and depend on the whole chain.

How do you compute the chance within a budget?

For hold-on-failure across L levels with B attempts, the tool uses the negative binomial distribution — the probability of achieving L successes within B independent trials at rate p.

Why does the expected cost feel so high?

Low success rates compound. A 20% rate over five levels with hold-on-failure averages 25 attempts; with reset-on-failure it can be vastly more because every failure can undo prior progress. Always check the failure rule before spending.

Can I model success-rate that changes per level?

This tool assumes a constant per-attempt rate. For tiered systems where higher levels are harder, run it once per tier with that tier's rate and sum the expected attempts and costs.

World of Warcraft Enchant & Gear Score Calculator

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Enchanting is gambling with your gold, and the failure rule changes the math dramatically. This calculator computes expected attempts and total cost to reach your target enchant level, plus the chance of hitting it within a fixed budget.

How it works

Each attempt succeeds with probability p, so the expected attempts for one level is 1 / p. Across L levels:

hold-on-failure:  expected attempts = L / p
reset-on-failure: expected attempts = (1/p^L − 1) / (1/p − 1)   [chain expectation]
expected cost     = expected attempts × cost per attempt

For hold-on-failure, the chance of reaching L successes within B attempts is the negative binomial CDF — the probability of seeing at least L successes in B independent Bernoulli trials.

Example and tips

A 25% enchant over four levels averages 16 attempts with hold-on-failure (4 per level). The same target with reset-on-failure averages far more, because any failure can cost you progress. Always confirm whether your game resets on failure, and prefer protection items or pity floors where available — they turn a punishing reset chain into a bounded cost.