Gaming · Idle and tycoon math
Tycoon game ROI calculator.
ROI = (value − cost) ÷ cost × 100, where value is the net income you collect over the horizon. In a tycoon game, net income is income minus upkeep. Example with invented numbers: 5 buildings at 8,000 earning 900 and costing 150 per hour make 3,750 net per hour, pay back in 10 h 40 min and return 125% over 24 hours.
Your numbers
Result
Working out the result.
How tycoon ROI is calculated
Harvard Business School Online gives return on investment as ROI = [(Financial Value − Project Cost) ÷ Project Cost] × 100, and counts every expense in the cost, not only the purchase price. In a tycoon game the financial value of a building is what it nets while it runs, so this page takes income minus upkeep for one unit, multiplies by the number of units and by your horizon, and compares that with the total purchase price. It also reports payback time (total cost ÷ net income per time unit) and the return per time unit, which lets you compare buildings with different running costs.
Worked example (illustrative numbers)
The prices are invented to show the method; they are not from any game. Five buildings cost 8,000 each, so 40,000 in total. Each earns 900 and costs 150 to run per hour, so net income per unit is 750 and the five make 3,750 per hour.
- Payback: 40,000 ÷ 3,750 = 10.67 hours, which is 10 h 40 min.
- ROI over 24 hours: 3,750 × 24 = 90,000 of value, so (90,000 − 40,000) ÷ 40,000 = 125%.
- Units for a target: to net 10,000 per hour you need 10,000 ÷ 750 = 13.3, so 14 units at a cost of 112,000.
ROI depends on how long you play
Because value is income collected over the horizon, the same buildings give a different ROI for each session length. With the numbers above, a 4-hour session returns -62.5% (a loss, since payback takes 10.67 hours), a 24-hour session returns 125% and a 48-hour session returns 350%. When you compare two buildings, use the same horizon for both, and use the “return per time unit” row if you do not know how long you will keep them.
What this calculator leaves out
It assumes steady income and fixed upkeep and ignores the price rising with each extra unit, capacity limits, staffing caps and any boost you get from reinvesting the profit. It also ignores the time value of money, which does not exist in most games. Use it to sort out whether a building is worth its upkeep and to size a purchase; use the upgrade payback time calculator when you only care how fast one purchase repays. For real businesses see the ROI calculator.
Common mix-ups
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Often assumedROI only compares the purchase price with the income, so upkeep can be ignored.
What the source saysThe Harvard Business School Online example adds the purchase (1,000 bars at 2) and the 100 transport together as total expenses before working out ROI, so every cost of running the project belongs in the number. [1]
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Often assumedA building has one fixed ROI, whenever I check it.
What the source saysThe formula divides (financial value minus cost) by cost, and financial value is the income collected over the period you count. A longer horizon collects more value, so the ROI of the same building rises the longer you keep it running. [1]
Checked against these sources on .
Frequently asked questions
How do I calculate ROI in a tycoon game?
Take net income per unit (income minus upkeep), multiply by units and your horizon to get value, subtract total cost, divide by total cost and multiply by 100. Five 8,000 buildings netting 750 each per hour return 125% over 24 hours.
What is a good ROI in a tycoon game?
Anything above 0% for your planned session means the buildings earn back more than they cost. Compare candidates over the same horizon and prefer the higher ROI, or the higher return per time unit if the session length is unknown.
Why is my ROI negative?
Either the session is shorter than the payback time, so the building has not repaid its cost yet, or upkeep is as large as income so net income is zero or below. The payback row shows which.
What is the difference between ROI and payback time?
Payback time is how long until net income covers the cost. ROI is the percentage gain or loss at the end of a chosen horizon. A building can have a short payback and still earn less in total than a slower one.
How many units do I need for a target income?
Divide the target net income by the net income of one unit and round up. To net 10,000 per hour with units that net 750 each, you need 14.
Does the calculator handle rising prices per unit?
No. It uses one price for every unit. If each copy costs more than the last, run it with the average price of the batch, or buy one at a time and repeat.
Sources
Retrieved
- Harvard Business School Online: How to Calculate ROI to Justify a Project — ROI = [(Financial Value - Project Cost) / Project Cost] x 100, with all expenses counted (read 2026-10-26)
- Penn State EME 460: Payback Period Analysis — payback period definition used for the payback row (read 2026-10-26)
Planning aid, example numbers are illustrative
Not affiliated with any game publisher. The worked example uses invented numbers. Real games change prices and rules in updates, so check your own in-game values. Nothing you type is sent or stored.