CS2 Case
House Edge
Calculator
Find out if your CS2 case opening site is fair — or taking you for a ride. Enter drop rates and prices to instantly reveal the real house edge.
The Calculator
Enter the case price and every item's drop rate + market value. Rates must sum to 100%.
House Edge % = ((Case Price − Expected Value) / Case Price) × 100
What is House Edge?
The math built into every case opening
What is House Edge?
House edge is the percentage of every dollar wagered that the site keeps as profit. A 10% house edge means for every $1.00 spent opening cases, you get back $0.90 in value on average.
How is it Calculated?
Multiply each item's drop rate by its market price, sum them all for Expected Value. Subtract EV from case cost, divide by case cost, multiply by 100. Our calculator handles this instantly.
What's a Fair Edge?
Below 7.5% is excellent for CS2. 7.5–11.6% is the industry norm. Above 11.6% is predatory. Valve's official CS2 cases run at ~85% house edge — third-party sites are significantly better.
Outcome Probability Simulator
See how lucky, average, and unlucky runs diverge over time. Auto-fills from the calculator above.
Simulates 500 independent runs and plots the 90th percentile (lucky), 50th percentile (average), and 10th percentile (unlucky) cumulative P/L at each open. The dashed line shows the mathematically expected outcome based on house edge alone.
Frequently Asked Questions
Everything you need to know about house edge
House edge is the percentage of every dollar spent opening cases that the site keeps as profit. It's calculated by comparing the expected value of items you can win (drop rates × item prices) against the cost of opening the case. A 10% house edge means for every $1.00 spent, you receive $0.90 in value on average.
Below 7.5% is considered very good and player-friendly. Between 7.5% and 11.6% is the industry standard for third-party CS2 sites. Anything above 11.6% is considered high and should be avoided. Valve's official CS2 cases have a house edge of roughly 85%+.
Multiply each item's drop rate percentage by its market price, then sum all results to get the Expected Value. Subtract EV from the case price, divide by case price, and multiply by 100. Our calculator above does this automatically — just enter the drop rates and prices. Note: all drop rates must sum to exactly 100%.
Yes, 10% falls within the industry standard range of 7.5% to 11.6% for CS2 case opening sites. While not exceptional, it's considered acceptable. If you find a site below 7.5%, that's significantly better value.
CS2 sites face higher operational costs: Steam marketplace fees, cryptocurrency transaction costs, maintaining item inventories, and less regulatory efficiency than licensed casinos. Traditional casinos operate at massive scale with centuries of optimization. However, reputable CS2 sites still offer far better odds than Valve's official cases.
Short-term, yes — RNG means some players will profit. However, the house edge mathematically guarantees that the site profits over enough openings. The more cases you open, the more your actual returns converge toward the negative expected value. Treat case opening as entertainment with a known cost, not an investment strategy.