Understanding this paradox is the key to balancing gacha systems that feel rewarding while protecting your economy.
Gacha has become ubiquitous in free-to-play games – no longer just for character acquisition in RPGs, but embedded in engagement features, reward systems, and monetization throughout your game. When designed well, gacha introduces fun randomness that drives engagement and allows you to monetize key items more deeply than direct purchase ever could.
But most teams balance gacha by looking at the wrong numbers.
What Players Get vs. What You Give Out
Here’s the insight that changes everything: What players walk away with after each pull is not what you’re giving out in gacha.
Let’s look at a simple example – a chest that gives out coins:
| Amount | Probability |
|---|---|
| 100 | 50.00% |
| 500 | 30.00% |
| 1,000 | 15.00% |
| 3,000 | 4.90% |
| 500,000 | 0.10% |
Looking at individual outcomes, it seems like players are getting wildly different things. One player walks away with 500,000 coins. Another gets 100. That feels unfair, right?
Wrong. Every player is getting exactly the same thing.
Every gacha pull gives out 50% of 100 coins, 30% of 500 coins, 15% of 1,000 coins, and so on. Calculate the expected value:
| Amount | Probability | Expected Value |
|---|---|---|
| 100 | 50.00% | 50 |
| 500 | 30.00% | 150 |
| 1,000 | 15.00% | 150 |
| 3,000 | 4.90% | 147 |
| 500,000 | 0.10% | 500 |
| Total | 100.00% | 997 |
Every single pull gives out exactly 997 coins. What differs between players is how those probabilities actualize. From an economy perspective, every gacha pull is identical.
This means when you’re balancing your gacha, you need to look at the entire probability distribution, not individual outcomes.
Why This Matters: Different Distributions, Same Value
Understanding expected value opens up interesting design choices. Here are three completely different gacha configurations that give out the exact same amount:
Configuration A: High Variance (Lottery-style)
| Amount | Probability | Expected Value |
|---|---|---|
| 100 | 50.00% | 50 |
| 500 | 30.00% | 150 |
| 1,000 | 15.00% | 150 |
| 3,000 | 4.90% | 147 |
| 500,000 | 0.10% | 500 |
| Total | 997 |
Configuration B: Uniform Distribution
| Amount | Probability | Expected Value |
|---|---|---|
| 787 | 20.00% | 157.4 |
| 987 | 20.00% | 197.4 |
| 997 | 20.00% | 199.4 |
| 1,007 | 20.00% | 201.4 |
| 1,207 | 20.00% | 241.4 |
| Total | 997 |
Configuration C: Consistent with Rare Spike
| Amount | Probability | Expected Value |
|---|---|---|
| 990 | 99.90% | 989.01 |
| 7,990 | 0.10% | 7.99 |
| Total | 997 |
All three configurations give out 997 coins per pull. But they create completely different player experiences and behaviors.
You’d never actually use Configurations B or C in practice—they’re here to illustrate the point. But understanding that wildly different structures can have identical expected values is crucial. Your economy cares about expected value. Your players care about experience.
You need to design for both.
The Two Numbers That Actually Matter
When balancing gacha, focus on these two critical points in your distribution:
1. The Worst Outcome (Usually the Most Common)
Here’s a fundamental truth about all gacha: The lowest value outcome will always be less than the average amount given out. And typically, the worst outcome is also the highest probability one.
This creates risk. If the worst outcome doesn’t feel valuable, you’ve damaged player trust.
Consider this scenario: A player spends $9.99 on a gacha pull and gets 100 coins—your worst outcome. Now imagine your shop sells a bundle for $4.99 that includes 100 coins. That player just paid 2x more for the same thing. That’s not a “bad luck” moment. That’s a design failure that kills repeat spending.
Your worst outcome must feel valuable relative to cost. Remember: the items you’re selling have no intrinsic value. It costs you nothing to ensure paying players walk away satisfied.
2. The Jackpot (The Dream)
The jackpot exists to create aspiration and excitement. It should be big enough to generate that “wow” moment when someone hits it. But it will be rare by design.
Here’s where teams often get this wrong: They fear the jackpot will break their economy.
Let’s do the math. In our example, 0.1% of pulls give 500,000 coins. If you have 1 million pulls:
- 1,000 jackpots distribute 500 million coins
- The other 999,000 pulls distribute 996 million coins
The jackpot accounts for roughly 33% of total coins distributed—but only for 0.1% of experiences. Yes, individual players who hit it will have their progression impacted. But something that occurs 0.1% of the time is marginal to your overall economy.
The jackpot’s value isn’t primarily economic – it’s psychological. It creates water-cooler moments, keeps players pulling, and makes your gacha feel exciting.
Could your biggest spender hit the jackpot? Yes. Should you design your entire system around that 0.1% × top 1% scenario? Absolutely not.
When designing your jackpot, don’t just think about probability in isolation – think about player experience over time. The key question isn’t “what’s the drop rate?” but rather “how many pulls until X% of players experience this?” A 0.1% drop rate sounds rare, but does that mean 10 pulls? 100 pulls? 1,000 pulls? The answer depends on how probability compounds over multiple attempts. To help with this, I’ve created a simple calculator that shows you how many pulls it takes for different percentages of your player base to hit specific outcomes. You can access it here. Use it to find the sweet spot where your jackpot feels aspirational but attainable – typically you want 50-75% of engaged players to experience it within a reasonable number of pulls for your game’s context.
Balancing Gacha: The Framework
Here’s how to think about gacha design:
Start with expected value. This is what you’re actually giving out. This is what your economy experiences.
Design the distribution around player experience. Consider:
- How often should players feel “unlucky”? (Don’t make it too often)
- How often should they feel “okay”? (This should be the majority)
- How rare should the dream outcome be? (Rare enough to excite, common enough that players believe it’s possible)
Validate the worst outcome. Ask yourself:
- Does this feel fair relative to cost?
- If players get this outcome 3 times in a row, will they keep pulling?
- How does this compare to direct purchase options?
If the worst outcome feels like a ripoff, your gacha won’t work – no matter how generous the expected value.
Make the jackpot aspirational. Calculate: How many pulls will it take for 50% of players to hit the top-tier outcome? If that number feels unreachable, you’ve lost the psychological benefit. If it’s too common, you’ve lost the excitement.
Trust the math. Your economy doesn’t care about individual outcomes. It cares about expected value across millions of pulls. Design your distribution to create the right player experience, then let probability do its work.
The Gacha Balancing Checklist
When designing or auditing gacha in your game:
✓ Calculate expected value – This is what your economy is actually giving out
✓ Stress-test the worst outcome – Does it feel fair relative to cost? To alternative purchase options?
✓ Make the jackpot meaningful – Big enough to create excitement, rare enough to feel special
✓ Choose variance deliberately – High variance for optional/excitement-driven gacha, lower variance for progression-critical systems
✓ Balance for both – Economy experiences expected value; players experience outcomes
The Bottom Line
Every gacha pull in your game gives out the same value. What players walk away with is just how probability actualizes for them individually.
Your job is to design a distribution where:
- The economy stays healthy (expected value)
- The worst outcome feels acceptable (player trust)
- The jackpot creates aspiration (player engagement)
Get these three things right, and your gacha will work. Mess up any of them – especially the worst outcome – and no amount of generous expected value will save you.
Design for the experience players have. Trust the math to handle your economy.
Alexandre Macmillan 