Example Data Table
| Scenario |
Level |
Start |
Target |
Discount |
Safeguard |
Recommended trials |
| Budget check | 140 | 10★ | 15★ | 0% | 12★ to 15★ | 1000 |
| Event planning | 160 | 12★ | 17★ | 30% | 12★ to 16★ | 2000 |
| High risk push | 200 | 17★ | 22★ | 5% | Off | 5000 |
Formula Used
The staged cost model uses item level, current star, discounts, safeguards, and destruction cost. The standard base attempt cost is:
0 to 9 stars: Cost = 1000 + level³ × (star + 1) ÷ 25
10 to 14 stars: Cost = 1000 + level³ × (star + 1)2.7 ÷ 400
15 stars and above: Cost = 1000 + level³ × (star + 1)2.7 ÷ 200
Effective cost: Base cost × (1 - total discount) × safeguard multiplier + flat fee.
Expected simulation: Each trial rolls success, failure, and destruction chances. Failures may hold, drop, or trigger chance time. Destruction adds replacement cost and resets the star level.
How To Use This Calculator
Enter the item level, current star, and target star. Add discounts, star catch boost, safeguard settings, replacement cost, and event rules. Choose a trial count. Press the submit button. Review the result summary first, then compare the per star table. Use CSV or PDF export to save your report.
Understanding Star Force Cost Planning
Star force upgrades are a staged improvement model. Each star represents a stronger item state. The calculator estimates the cost needed to move from one star count to another. It also models risk, because higher stages may fail, drop, or destroy the item.
Why Cost Changes By Star
The attempt price rises with item level and target stage. A low level item costs less because the cubic level factor is smaller. A higher star also adds pressure through a power factor. This creates a curve, not a straight line. Small changes near the top can create large cost swings.
Risk And Safeguards
Advanced planning is more than reading one price. You should include success rate, fail behavior, boom chance, replacement cost, and safeguard rules. Safeguard can remove destruction for selected stages, but it usually raises each protected attempt. Events can reduce cost, stop star drops, or guarantee certain milestone upgrades.
Simulation Value
Expected cost is hard to judge by hand. A single lucky run can finish cheaply. A bad run can spend much more. This tool uses repeated trials to show an average, median, high case, completion rate, attempts, and booms. These values help you set a budget before you start.
Physics View Of The Model
Although this is an upgrade economy tool, the layout follows a physics style. Inputs define a system. Probabilities define possible state transitions. Every attempt moves the item to a new state. The final report shows energy like cost flow across the upgrade path.
Best Use Cases
Use the calculator before expensive upgrades. Compare a normal day with a discount event. Try safeguard on and off. Add replacement value if destruction matters. Adjust trial count for smoother averages. Check the per star table to see where most cost gathers.
Planning Tips
Start with your current star and real target. Use the item level from your equipment. Keep discounts realistic. Do not ignore boom cost at higher stars. Run several scenarios and save the reports. A careful estimate will not remove luck, but it can reduce poor decisions.
Review the table after every run. Costly stages show where waiting for events may give the largest practical savings overall for your gear.
FAQs
What does this calculator estimate?
It estimates upgrade cost from a current star to a target star. It includes success chance, failure behavior, destruction risk, discounts, safeguard cost, replacement cost, and repeated simulation results.
Why are results different from one run to another?
The calculator uses probability simulation. Changing the seed, trial count, or settings can change the output. More trials usually make averages smoother, but chance still creates a range.
What is the safeguard option?
Safeguard protects selected star stages from destruction. The removed destruction chance becomes failure chance. The protected attempt cost is multiplied by the safeguard multiplier.
What does chance time mean?
Chance time makes the next attempt succeed after two failed attempts. This tool lets you include that rule for more realistic staged upgrade planning.
Can I model discount events?
Yes. Enter an event discount and any extra discount. You can also turn on milestone guarantees or disable destruction and star drops under selected ranges.
What is replacement cost?
Replacement cost is the value added after destruction. Use it for item copies, backup materials, transfer cost, or any extra cost needed to continue after a boom.
Why is the target adjusted sometimes?
The target must be higher than the current star. If a lower target is entered, the script moves it to the next valid star so the calculator can run.
Can I download the results?
Yes. The CSV button downloads detailed table data. The PDF button saves the main summary after a result is calculated.