Forge of Empires Great Building Calculator - 1.9 Thread FP Investment

The Mathematical Foundation of Forge of Empires Investing

To master Forge of Empires, you must stop thinking of Great Buildings (GBs) as simple structures. They are **Forge Point sinks** that convert time and social capital into city-wide bonuses. The 1.9 Thread is the standard mathematical agreement that allowed the game to scale. At its core, the 1.9 thread is built on the Level 80 Arc bonus.

When your Arc reaches level 80, it provides a 90% bonus on all Great Building rewards. This means if a building offers a 100 FP reward for the first place spot, a player with a level 80 Arc receives 190 FPs. By contributing exactly 190 FPs to your building, they "break even"-they spend 190 and get 190 back, plus medals and blueprints. As the owner, you get 190 FPs toward your level-up without spending a single point of your own.

**Why accuracy matters:** A single point of miscalculation can leave you vulnerable to neighbors who track your buildings. If you are 1 FP short of a "lock," a sniper can invest half of the remaining points and steal the spot, costing you the reward and potentially hundreds of FPs in lost guild contributions.

How to Use This Tool?

Using the **FoE GB Calculator** is straightforward, but you must be precise with the numbers from your game screen. Follow these steps to ensure a perfect lock:

1. Identify the Total Cost: Look at the progress bar of your Great Building. The number on the right (e.g., 2450) is the total cost for that level.
2. Find the P1 Base Reward: Click on the first place chest icon. Note the number of Forge Points it rewards (this is the *base* reward, not the 1.9 reward).
3. Enter Existing Contributions: If you've already put points in or if a neighbor has "sniped" some points, enter those in the respective fields.
4. Check the Multiplier: Standard threads are 1.9, but elite guilds use 1.92 or 1.94. Adjust accordingly.
5. Execute: Click "Calculate Lock." The tool will tell you the exact "Safe Point" for you. You must add points until you reach that safe point before you post the building in your guild thread.

Mastering the Sweet Spot

The "Sweet Spot" is the most exhilarating phase of Great Building progression, typically occurring between levels 30 and 65. During this phase, the building's rewards for P1 and P2 are so high that they cover nearly the entire cost of the level. In many cases, you only need to contribute 5-50 FPs of your own to "prime" the building for P1 and P2 to be locked.

Many players make the mistake of over-priming during the sweet spot. They see a level that costs 2000 FPs and they automatically put in 500 FPs because they are used to the early levels. This is a massive waste. My calculator will show you if a spot is "lockable" with 0 contribution from you. If it is, save your FPs for the "Dead Zone" (levels 1-25 and 70+), where the owner has to cover 60%+ of the costs.

If you have enough blueprints, you can "loop" levels in the sweet spot. I've often leveled my Arc from 40 to 60 in a single hour by having guildmates ready to take spots the second I opened a new level. The sweet spot is how you gain thousands of ranking points in a day.

Ethics & Math of Sniping

Sniping is the act of investing in a neighbor's Great Building for a profit. To a sniper, this calculator is a **profitability sensor**. By entering a neighbor's building data, the sniper can see if a 1.9 spot is "open." If the owner hasn't primed the building correctly, the sniper can put in fewer points than the 1.9 reward and still take P1 or P2.

For example, if P1 rewards 1000 FPs at the 1.9 rate, but the owner hasn't added points, a sniper might only need to add 800 FPs to lock the spot if the remaining budget is small. The sniper makes a 200 FP profit, and the owner loses a 1.9 donation. Is it ethical? In neighbors, yes. In guilds, it-s usually an instant ban. My advice: **Always be the sniper, never the target.** Use this tool to lock your own spots before you harvest your city.

The Cultural Evolution of Great Buildings in FoE

If you played Forge of Empires in 2012, the landscape was unrecognizable. Back then, Great Buildings were symbols of prestige that only the "whales" or the extremely patient could afford to level. There was no Arc. There were no 1.9 threads. Players relied on "Swap Threads," where you would donate 10 PFs to a guildmate's building in hopes they would return the favor. It was slow, inefficient, and prone to drama when someone forgot to pay back.

The introduction of **The Arc** in the Future Age transformed FoE from a city-builder into a mathematical optimization game. Suddenly, players had a way to multiply their Forge Point wealth. Once the community realized that a level 80 Arc allowed for a break-even 1.9 investment, the "Arc Era" began. This cultural shift centralized guild activity around these threads, making guilds that didn't adopt the system obsolete almost overnight. Today, a guild without a robust 1.9 thread is essentially a graveyard for your FPs.

My calculator is built to respect this history. It handles the 1.9 standard, but I-ve also included the ability to change that multiplier because the game is evolving again. We are entering the "Power Arc" era, where level 140+ Arcs are becoming common, pushing threads to 1.92 and beyond. Being able to pivot your math as your guild grows is essential for staying in the top 1% of your world-s rankings.

The Guild Battlegrounds (GBG) Synergy

While the FoE GB Calculator helps you spend Forge Points efficiently, **Guild Battlegrounds** is where you earn them. In the current game meta, GBG is the primary engine of FP generation. An active player in a Diamond League guild can easily generate 500 to 2,000 Forge Points per day through battles. These FPs aren't just for your inventory; they are the fuel for your Great Building levels.

This creates a powerful "Synergy Loop." You use your military GBs (Zeus, Cathedral of Aachen, Castel del Monte) to increase your attack stats, which allows you to fight more in GBG. The FPs you earn in GBG are then funneled back into your Arc or your military GBs using my calculator. Each level of Zeus makes the next GBG season more profitable. It is a compounding interest curve that rewards those who use math to decide their next building level.

Without a calculator, you might waste these hard-earned GBG points by putting them into a building that isn't yet lockable. I-ve seen players dump 1000 FPs into a level 70 Alcatraz, only to be sniped for 200 PFs by a neighbor because they didn't realize they were 1 FP away from a safe point. Don't be that player. Every FP you earn in the heat of battle should be placed with surgical precision.

The Mathematical Reality of Arcs Beyond Level 80

Many players ask: "Is it worth taking my Arc to 100, 120, or even 180?" The answer depends on your goal. If you are an investor who spends hours a day sniping the neighborhood, a high-level Arc is a gold mine. At level 180, your bonus is over 100%. This means when you donate to a 1.9 thread, you are actually **making a profit** of 10% on every Forge Point you spend.

However, the cost to reach level 180 is astronomical-hundreds of thousands of Forge Points. Using my calculator to plan these high-level jumps is mandatory. In the "Dead Zone" between level 80 and 100, the owner's contribution requirement spikes significantly before the sweet spot kicks in again at higher levels. Most players who attempt to reach 180 without a plan end up stalling in the level 90s because they didn't budget for the priming costs. This tool helps you see the "Total Owner Cost" which is the most important metric for high-level players.

The Deep History: Why the Arc Changed Everything

If you played Forge of Empires in its infancy (circa 2012-2013), you remember a world of scarcity. Great Buildings were luxury items reserved for the upper echelon of the global rankings. There was no such thing as a "1.9 thread." We used **Swap Threads**, which were essentially a "I pat your back, you pat mine" system. While social, they were mathematically disastrous. You would put 10 FPs into a neighbor's building, and they would put 10 into yours. This meant you were effectively paying 100% of the cost for every level. The idea that a single level could cost you zero points felt like magic.

Then came the Future Age and **The Arc**. Initially, many players didn't understand its power. They saw it as another building to level. But the mathematics-heavy guilds in the Beta and EN servers soon realized that the 90% bonus at level 80 was a "Singularity." It created a closed loop where Forge Points could be recycled without loss. This didn't just change how we played; it changed the very nature of competition. Guilds that adopted the Arc early became superpowers, dictating the GvG and GBG landscapes for years. Today, having a level 80 Arc isn't a badge of honor; it's the bare minimum required to actually "play" the mid-game.

Global Server Metas: US vs EN vs Beta

As Aurangzeb Abbas, I've tracked the progression rates across different global servers. It's fascinating how localized cultures develop. On the **US servers** (like Arvahall or Dunarsund), the 1.9 thread is almost a sacred ritual. There is a high level of accountability, and "locking" without priming is seen as a social sin. However, on the **Beta server**, where the newest features are tested, the meta is often much more experimental. We see 1.94 or even 1.96 threads as the standard because players there have had Arcs at level 150 for years.

The **International (EN) servers** often sit somewhere in between. They have a massive population of long-term players who have accumulated millions of Forge Points. In these worlds, the "Sniping Culture" is much more aggressive. On EN, if you leave a building unprimed for more than five minutes, you *will* be hit. This tool was designed with that pressure in mind. It calculates the safety margin so you can move from "Calculation" to "Posting" in under ten seconds, minimizing the window of vulnerability.

The Psychology of the 'Arc 80' Plateau

Why do so many players quit in the level 60-70 range of their Arc? It's what I call the **Owner Cost Peak**. Even though the rewards are high, the base cost of these levels is so astronomical that you still find yourself contributing 500+ FPs just to lock P1. This feels like moving through molasses. Many players see these costs and compare them to the easy levels 1-20, feels like they've hit a wall.

However, once you cross level 80, the scaling shifts. The "Sweet Spot" begins, and suddenly your personal contribution drops from 500 FPs to 50 FPs. This reward for persistence is what hooks long-term players. If you are currently in the level 65 struggle, use my calculator to look at level 85. Seeing that the future cost is effectively $0$ is the best motivation to keep pushing your daily harvest into that Arc.

Great Building Tier List: Primary vs Secondary

Not all GBs are created equal. Using Forge Points efficiently requires prioritizing which building to put in the thread. I categorize them into three tiers:

• Tier 1 (The Holy Trinity): The Arc, Alcatraz, and Castel del Monte. These provide the economy, the military, and the FP generation required to sustain all other growth.
• Tier 2 (The Multipliers): Chateau Frontenac (for quest rewards), Cape Canaveral (for pure FPs), and Himeji Castle (for the combat spoils). These should only be leveled once your Tier 1 structures are in their respective sweet spots.
• Tier 3 (The Specialists): Seed Vault, Space Carrier, and Blue Galaxy. These are for end-game players who have already maxed their primary needs and are looking for niche resources like special goods or double harvests.

Using the **FoE GB Calculator** on a Tier 3 building is a luxury. If your Arc isn't level 80 yet, any point you put into a Blue Galaxy is a point you are stealing from your future self. My advice? Follow the math, not the shiny artwork.

Advanced Arc Group Management

If you are a guild leader, you aren't just managing players; you are managing a **Liquidity Pool**. A 1.9 thread only works if there is enough "float" (unspent FPs) in the guild to take spots instantly. If the thread stalls, your players become vulnerable to neighbors.

To prevent this, I recommend setting "Tiered Threads." Have a dedicated 1.9 thread for buildings under level 30, and a "Power Thread" (1.92+) for high-level buildings. This ensures that the high-FP investors are incentivized to keep their FPs in-guild rather than sniping neighbors. My calculator's custom multiplier field is essential for these tiered systems. You can tell your 1.92 investors exactly what they need to put in to remain profitable while supporting the guild treasury.

The Impact of Events on FP Inflation

In 2024 and beyond, InnoGames has drastically increased the power of Event Buildings. A single 4x4 event building can now provide 20-30 FPs per day, whereas a level 10 Hagia Sophia (which takes 3,800 FPs to build) only provides 6. This has led to massive "FP Inflation." Five years ago, 1,000 FPs was a huge fortune. Today, it's what you make in a morning harvest.

How does this affect your GB leveling? It means you should be aggressive. Because FPs are more common, you can afford to "over-pay" on certain levels to speed up your Arc progression. The opportunity cost of waiting three days to save 100 FPs is now higher than just spending the points and getting to the next level. This calculator helps you see that "Owner Cost" so you can make those strategic decisions with confidence.

The Math of Medals and Land Expansion

Most players forget that GBs aren't just for FPs and Stats; they are for Land. To unlock the final expansions in the Space Ages, you need tens of millions of medals. You will never get these through PvP towers or normal play. You get them by taking P4 and P5 spots on high-level GBs in 1.9 threads.

Investors often take P4 and P5 at 1.9 even if they lose 2-3 FPs in the process. Why? Because the medal reward for those spots can be 50,000+. To an end-game player, 3 FPs is a fair price to pay for 50k medals. Use this tool to find those "Medal Snipes" where the owner has already primed the building, and you can secure life-changing amounts of medals for the cost of a few forge points.

GB FP Costs Table (30+ Buildings Level 1-10)

For those planning their early-game strategy, here are the total FP costs for popular Great Buildings from Level 1 to Level 10. Note how the costs scale rapidly as you move into later ages.

These numbers prove why the **Arc Strategy** is the only viable path. Trying to fund a level 10 Himeji Castle (8,200 FPs) with just your daily harvest would take months. With 1.9 threads, you can cut that time by 80%.

Common Pitfalls to Avoid

Even with a calculator, players fail. Here are the most common ways you can lose Forge Points while leveling:

• Double Priming: Checking the math, adding the points, then getting distracted and adding more "just to be safe." This is an FP profit for your investors and an FP loss for you.
• Ghost Investments: Forgetting about neighbors who put in 1 or 2 FPs. These tiny contributions change the lock math. Always refresh your building screen before using the final numbers.
• The "Self-Lock" Trap: Forgetting that you, as the owner, cannot lock your own spots. You only prime the spots for others to lock. If you put in too much, you leave a "gap" where no one can overtake you, but you've spent more than necessary.
• Blueprints Depletion: Leveling so fast that you run out of blueprints for the next level. Always secure P1 spots in your guild's 1.9 threads to replenish your stock.

Mastering these pitfalls will save you hundreds of Forge Points per session. Consistent precision is what separates average players from the top 1% in any server.