Foe Great Buildings Calculator

Your expert tool for optimizing Great Building investments in Forge of Empires.

Great Building Investment Calculator

Calculation Results

Intermediate Values & Spot Costs

This table shows the costs for investors to secure each reward spot and the remaining cost for the owner. This is a core function of any professional foe great buildings calculator.

Position	Total Reward (FP)	Secured Cost (FP)	Owner’s Remaining Cost (FP)
Please enter valid levels and click ‘Calculate’.

Breakdown of costs and rewards per position for the specified level range.

What is a FoE Great Buildings Calculator?

A foe great buildings calculator is an essential tool for any serious Forge of Empires player who wants to efficiently level up their Great Buildings (GBs). It automates the complex mathematics involved in “1.9 threads” and other contribution-based leveling strategies. Instead of manually calculating how many Forge Points (FPs) an owner needs to add to their GB to make reward spots “safe” for investors, this calculator does it instantly. The primary goal is to minimize the owner’s FP expenditure by maximizing contributions from other players who, in turn, get rewarded with FPs, medals, and blueprints.

Anyone aiming for rapid city growth, from mid-game players starting their first Arc to end-game veterans leveling GBs past 100, should use a foe great buildings calculator. A common misconception is that these tools are only for players in “1.9 guilds.” While they are perfect for that, they can be customized for any contribution rate (e.g., 1.85, 1.92, or even custom swap threads), making them universally useful for smart FP management. Using this tool is the difference between slow, expensive leveling and fast, cost-effective growth.

FoE Great Buildings Calculator: Formula and Mathematical Explanation

The core logic of a foe great buildings calculator revolves around a few key formulas. The primary goal is to calculate the amount an investor needs to contribute to “secure” a reward spot at a specific rate, and subsequently, the remaining cost for the GB owner.

1. Secured Cost for an Investor: This is the amount an investor contributes to break even or profit based on their Arc bonus. The formula is:

Secured Cost = round(Spot Reward / (1 + (Investor Arc Bonus / 100)))

2. Owner’s Total Cost: This is the total FPs required for the level, minus the sum of all secured contributions from investors.

Owner's Cost = Total Level Cost - Sum of all Secured Costs

Here is a step-by-step derivation: The calculator first looks up the total FP cost and the reward for each of the top 5 positions for a specific GB level. Then, for each position, it applies the “Secured Cost” formula to determine what an investor participating in a 1.9 (or other rate) thread would pay. Finally, it subtracts all these investor contributions from the level’s total FP cost to determine the final amount the owner must pay themselves. This makes our tool a very precise foe great buildings calculator.

Variables Table

Variable	Meaning	Unit	Typical Range
Total Level Cost	The total Forge Points required to complete one level of a GB.	Forge Points (FP)	50 – 10,000+
Spot Reward	The base FP reward for securing a specific position (e.g., P1, P2).	Forge Points (FP)	5 – 1,500+
Investor Arc Bonus	The percentage bonus an investor gets on rewards from their Arc GB.	Percentage (%)	0% – 120%
Owner’s Cost	The net Forge Points the owner must contribute after all investor spots are filled.	Forge Points (FP)	Varies Greatly

Practical Examples (Real-World Use Cases)

Example 1: Leveling an Arc from 79 to 80

A player wants to complete the final, most crucial level of their Arc. The total cost is 1,937 FP. They are in a standard 1.9 guild, so investors have a 90% Arc bonus. Using the foe great buildings calculator:

• Inputs: GB = The Arc, Level From = 79, Level To = 80, Investor Arc Bonus = 90%.
• Outputs: The calculator finds the rewards for spots P1-P5 (e.g., 990, 330, 105, 35, 10 FP).
• Calculation: It determines the secured costs: P1 needs 521 FP (990 / 1.9), P2 needs 174 FP (330 / 1.9), and so on for P3-P5.
• Financial Interpretation: The total secured contributions are 832 FP. The owner’s cost is 1,937 – 832 = 1,105 FP. This is a massive saving compared to paying the full 1,937 FP themselves. Check out our guide to understanding the Arc bonus for more details.

Example 2: Early Level of a Château Frontenac

A player wants to level their Château Frontenac (CF) from 14 to 15. The cost is 1,098 FP. Their guild uses a 1.85 rate for non-Arc investors.

• Inputs: GB = Château Frontenac, Level From = 14, Level To = 15, Investor Arc Bonus = 85%.
• Outputs: The foe great buildings calculator finds the rewards (e.g., 295, 95, 30, 10, 5 FP).
• Calculation: It calculates secured costs at the 1.85 rate: P1 needs 159 FP (295 / 1.85), P2 needs 51 FP (95 / 1.85), etc.
• Financial Interpretation: The total investor contribution is 236 FP. The owner’s cost is 1,098 – 236 = 862 FP. This demonstrates how the calculator is adaptable and vital for planning even at lower levels or with different contribution rates.

How to Use This Foe Great Buildings Calculator

Using this foe great buildings calculator is a straightforward process designed for efficiency. Follow these steps for an accurate calculation:

1. Select Great Building: Choose the GB you are leveling from the dropdown menu. The list contains all available GBs in the game.
2. Enter Levels: Input the ‘Current Level’ you are starting from and the ‘Target Level’ you wish to reach. For single-level calculations, set Target Level to Current Level + 1.
3. Set Investor Arc Bonus: Enter the bonus percentage of the players who will be contributing. For standard 1.9 threads, this is 90%. Adjust it for 1.8 threads (80%), 1.85 threads (85%), or any other custom rate.
4. Add Owner’s Investment (Optional): If you have already put some FPs on the current level, enter that amount in the ‘Owner’s Current Investment’ field. This will be subtracted from your final cost. A good FoE leveling strategy often involves ‘pre-loading’ some FPs.
5. Read the Results: The calculator instantly shows the ‘Total Owner’s Cost’ in the highlighted box. The table below breaks down the secured cost for each of the five reward positions, which you can announce in your guild’s thread. The chart provides a quick visual of rewards versus costs.

Decision-Making Guidance: Use the output to decide if you have enough FPs to start leveling. The “Owner’s Remaining Cost” for each spot tells you exactly how many FPs you must add to secure that position for an investor. For example, to open P1, you must add the amount shown in the “Owner’s Remaining Cost” column for the P1 row.

Key Factors That Affect Foe Great Buildings Calculator Results

The results from any foe great buildings calculator are influenced by several dynamic factors. Understanding them is key to mastering your GB strategy.

• 1. Investor’s Arc Bonus Rate: This is the most significant factor. A higher bonus rate (like 90% for 1.9) means investors pay less for a spot, which in turn increases the owner’s cost. A lower rate (e.g., 80% for 1.8) means investors pay more, reducing the owner’s cost.
• 2. Great Building and Level: Each GB has a unique cost and reward structure per level. Higher levels are exponentially more expensive but also offer larger rewards, which can attract more investors and reduce the owner’s relative cost. Some buildings are more profitable to level than others; see our guide on the top 10 Great Buildings.
• 3. Total FP Cost of the Level: The fundamental cost is a hard limit. No matter how high the investor contributions, the owner is always responsible for the difference. A robust foe great buildings calculator always starts with this number.
• 4. Number of Secureable Spots: In very low levels, only 1 or 2 spots might offer a reward. At higher levels, all 5 spots are valuable. If fewer spots are taken by investors, the owner’s cost burden increases proportionally.
• 5. “Sniping” and Out-of-Thread Contributions: The calculator assumes an orderly contribution process. If another player “snipes” a spot by contributing just enough to overtake someone, it disrupts the calculation. A good strategy is to only add enough FPs to secure one spot at a time. Learn more about how to secure a spot in FoE threads.
• 6. Owner’s Pre-investment: Adding your own FPs before seeking investors reduces the final amount you need to add to secure spots. This is a common tactic used to prepare a level for a 1.9 thread.

Frequently Asked Questions (FAQ)

1. What is a “1.9 thread”?

A “1.9 thread” is a system where players with a Level 80 Arc (which gives a 90% bonus on rewards) contribute to each other’s Great Buildings. They contribute 1.9 times the base reward for a spot and, thanks to their Arc, get that exact amount back when the GB levels. Our foe great buildings calculator is perfect for this.

2. What does it mean to “secure” or “lock” a spot?

Securing a spot means the GB owner has contributed enough of their own FPs so that the remaining amount needed for a specific reward position is exactly what an investor would pay at the agreed-upon rate (e.g., 1.9). This prevents other players from “sniping” the spot for a lower cost.

3. Can I use this calculator if I’m not in a 1.9 guild?

Absolutely. You can set the “Investor’s Arc Bonus” to any percentage. If your guild uses a 1.8 rate, set it to 80%. If you have a friend with a Level 60 Arc (61% bonus), you can enter 61% to see what they would need to pay.

4. Why is the Owner’s Cost sometimes negative?

A negative owner’s cost can occur at very high GB levels when using a low investor bonus rate. It means the sum of what investors pay is MORE than the total cost to level the building. This is rare but results in a direct FP profit for the owner.

5. How accurate is this foe great buildings calculator?

This calculator uses the official cost and reward data for all Great Buildings and levels. The mathematical formulas for calculating secured costs and owner contributions are standard across the Forge of Empires community, ensuring high accuracy.

6. Does the calculator account for Blueprints and Medals?

This calculator focuses purely on the Forge Point (FP) economy, as that is the primary concern for leveling costs. Blueprints and medals are additional rewards for investors but do not affect the FP calculations for the owner.

7. What’s the best strategy for a new player using this tool?

New players should focus on getting their Arc. Use the calculator to plan the leveling of your first key GBs like Zeus or Castel del Monte. Even if you don’t have a 1.9 thread, you can use it to negotiate fair swaps with guildmates. Our FoE city planner can also help you decide which GBs to build.

8. Why does the ‘Copy Results’ button exist?

This feature is for convenience. It formats the results into a clean text message that you can paste directly into your in-game guild chat or message thread to announce which spots are available on your GB and for how many FPs.

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