How MapleStory upgrade budgets work

Know your upgrade odds

A complete three-line potential roll is one attempt. Expected cubes = 1 / p. The chance of reaching a fixed target within n rolls is 1 − (1 − p)^n. Percentile budgets round up to the smallest whole cube count reaching the stated success chance.

For a Legendary level-150 weapon, Glowing Cubes targeting ATT ≥21% take about 146.7 cubes on average, with 236 cubes for 80% and 438 for 95%. With the default 12 million mesos per cube and 450,000 reveal fee, the 95% budget is 5.4531 billion mesos.

Tier-up and potential reroll stages are modeled as independent geometric waiting times. The total average is the sum of stage averages. Total percentiles use the distribution of the full chain, not the sum of individual percentiles. The cube which raises the tier is counted as a tier-up attempt, followed by fresh target rolls; the model does not credit target lines on that tier-up cube.

Potential line tables follow the KMS-based tables updated 2023-11-14. Glowing maps to Red, Bright to Black, Mystical to Occult, Hard to Master, and Solid to Meister. Tier-up rates follow the captured community estimates, including their uncertainty; DMT doubles Glowing and Bright tier-up rates only. GMS rates may differ. Accessory uses the ring pool; badge uses heart as a proxy.

Three lines within a cube are conditional, not independent draws from an unchanged pool. Category limits remove excluded lines before subsequent draws. Archived displayed percentages are rounded; the calculator retains the source denominator of 100 percent. At level 160 or above, the model adds one percentage point to stat, all-stat, attack and HP lines, matching the archived approximation. The archived base pool is also used for levels 71–119; lower-level results are approximations.

Some cube/tier combinations have no archived line table. Any remains available for tier-up-only calculations, without inventing potential probabilities. A target that cannot occur is shown as unreachable. Changing a selection clears an advanced probability override. A custom cube price replaces the shop component, with an optional separate reveal fee.

Star Force exact averages solve an absorbing Markov chain, including destruction resets and historical Chance Time. Cost and boom percentiles, minima, maxima and the histogram are seeded Monte Carlo estimates, not guaranteed limits. Both outcomes are sampled in the same session. Trial count and seed are shareable. Extreme targets have a bounded simulation workload; when exceeded, only exact averages are shown until a smaller simulation is requested.

Star Catch multiplies success chance by 1.05. MVP discounts apply through the attempt from 15 to 16 stars. MVP and 30% event discounts are additive. Safeguard surcharges, restoration stars and probability tables depend on region. GMS 30 Stars and KMS permit 30-star targets; historical and TMS rules permit 25. The +2-stars event applies at 10 stars and below in historical/TMS rules. The 30% boom reduction event applies through 21 stars in the modern rules. Shining combines 30% off with 5/10/15.

The archived Star Force page has no active PC-room control and fixes its sauna flag off. The separate historical no-boom switch here reproduces the archived sauna function for 12–14 stars; it is not a PC-room discount. Replacement equipment purchase prices are excluded. Percentiles for destroyed items use linear interpolation, so they can be fractional.

Probability and rule sources

• Nexon KMS cube probability and exclusion rules
• Archived KMS-based potential tables (table date: 2023-11-14; captured: 2026-10-14)
• Cube prices, community tier-up rates and DMT mapping
• Regional Star Force cost and success tables (captured: 2026-10-14)
• Star Catch, discounts, events and destruction recovery rules

Probability tables are fixed snapshots. Community tier-up estimates are not official GMS guarantees. Fan-made calculators are not affiliated with Nexon.

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Reference interfaces: MathBro Cubing · MathBro Star Force. Our table snapshots and formulas are listed in methodology.