CS2 Luck Analyzer
Analyze your CS2 case opening results against mathematical expectations. Input your unboxing history and discover whether you're statistically lucky, unlucky, or running exactly at expected averages. Uses real probability data to calculate your luck score.
🎯 Luck Analysis Calculator
Enter your case opening results to calculate your luck score
Step 1: Total Cases Opened
Step 2: Your Results by Rarity
Enter how many items of each rarity tier you received. Expected values will update based on case count.
Your results are exactly as expected.
Detailed Breakdown
| Rarity | Expected | Actual | Difference | Deviation |
|---|
📊 Understanding Your Results
Your luck score is calculated using z-scores and standard deviation from expected values. A score of 0 means exactly average luck. Positive scores indicate better-than-expected results, while negative scores indicate worse-than-expected results. The analysis uses binomial distribution probability models based on Valve's disclosed CS2 drop rates.
How the Luck Analyzer Works
The CS2 Luck Analyzer uses statistical methods to compare your actual case opening results against mathematically expected outcomes. By analyzing the deviation from expected values across all rarity tiers, the tool calculates a comprehensive luck score that tells you whether you're running above, below, or exactly at expected averages.
The Mathematics Behind Luck Analysis
Case opening in CS2 follows a binomial distribution - each case has fixed probabilities for each rarity tier, and outcomes are independent. For any given number of cases, we can calculate the expected number of items at each rarity using simple multiplication:
- Expected Mil-Spec: Cases × 0.7992 (79.92%)
- Expected Restricted: Cases × 0.1598 (15.98%)
- Expected Classified: Cases × 0.032 (3.20%)
- Expected Covert: Cases × 0.0064 (0.64%)
- Expected Rare Special: Cases × 0.0026 (0.26%)
The luck score is derived from z-scores, which measure how many standard deviations your results are from the expected mean. A z-score of +1 means you're one standard deviation above average (luckier than ~84% of players), while -1 means one standard deviation below (unluckier than ~84% of players).
Understanding Variance
It's crucial to understand that variance is normal and expected. Even with perfectly fair odds, results will fluctuate significantly, especially with smaller sample sizes. Opening 50 cases and getting no Covert items isn't necessarily "unlucky" - the probability of that happening is actually about 73% due to the low base odds (0.64% per case).
The Luck Analyzer accounts for sample size when calculating your luck score. Getting one knife in 100 cases is much luckier (statistically speaking) than getting one knife in 1000 cases, even though both exceed expected values. According to the Law of Large Numbers, your results will converge toward expected values as your sample size increases.
What Your Luck Score Means
The luck score ranges from approximately -100 to +100, with 0 representing perfectly average luck:
- +75 to +100: Extremely Lucky - Top 1% of results
- +50 to +74: Very Lucky - Top 5% of results
- +25 to +49: Lucky - Top 15% of results
- +10 to +24: Slightly Lucky - Above average
- -10 to +10: Average - Normal variance range
- -24 to -10: Slightly Unlucky - Below average
- -49 to -25: Unlucky - Bottom 15% of results
- -74 to -50: Very Unlucky - Bottom 5% of results
- -100 to -75: Extremely Unlucky - Bottom 1% of results
Weighting by Rarity Value
The analyzer weights deviations by rarity importance. Getting an extra knife has a much larger impact on your luck score than getting extra Mil-Spec items, because:
- Rarer items have higher financial value
- Rarer deviations are more statistically significant
- Players care more about high-tier outcomes
This weighted approach gives you a luck score that better reflects how you'd actually feel about your results, rather than treating all tiers equally.
Interpreting Your Results Responsibly
Past Luck Doesn't Predict Future Results
One of the most important things to understand about probability is that past results have no influence on future outcomes. This is a fundamental principle known as independence in probability theory. If you've been unlucky for 500 cases, the 501st case still has exactly the same odds as if you'd been lucky. According to research from the National Center for Biotechnology Information (NCBI), believing otherwise is the gambler's fallacy, a cognitive bias that leads to poor decision-making.
Your luck score reflects what has already happened. It cannot and should not be used to predict what will happen next. A low luck score does not mean you're "due" for good results.
Sample Size Matters
The reliability of your luck score increases with sample size. With only 10-20 cases, extreme luck scores are common and don't necessarily reflect anything meaningful. Statistically, with 385 cases, you should expect roughly one knife (on average), but many players will get zero, and some will get multiple - all within normal variance.
Consider your luck score more reliable at:
- 50+ cases: Starting to show patterns
- 100+ cases: Moderately reliable indicator
- 500+ cases: Highly reliable assessment
- 1000+ cases: Very accurate luck measurement
Emotional vs. Statistical Luck
Sometimes there's a disconnect between how lucky you feel and how lucky you statistically are. Getting 10 Mil-Spec skins you don't like might feel unlucky, but it could be statistically average. Conversely, getting one skin you love might feel incredibly lucky even if the statistics say otherwise.
This tool measures statistical luck based on drop rates. It doesn't account for the subjective value you place on specific items, whether you got StatTrak versions, float values, or pattern variants.
Related Tools
For comprehensive CS2 case analysis, combine the Luck Analyzer with our other tools:
- Case Odds Calculator: Calculate exact probabilities before opening cases
- Streak Calculator: Understand dry streak and win streak probabilities
- ROI Calculator: Calculate expected value and return on investment
- Profit Calculator: Track actual profit/loss from your sessions
- Rarity Visualizer: See drop probabilities visualized
- Loot Distribution Calculator: See expected item breakdown across all tiers
- Case Odds Explained: Comprehensive guide to CS2 probability mechanics
Frequently Asked Questions
Is this luck analyzer accurate?
Yes, the analyzer uses mathematically correct calculations based on Valve's officially disclosed CS2 drop rates. The z-score calculations and percentile estimates follow established statistical methodology. However, "luck" is being measured purely in statistical terms - deviation from expected values - not subjective satisfaction with results.
Why does my luck score seem different from how I feel?
The analyzer weights all items within a tier equally, but you might value certain skins more than others. Getting 5 Mil-Spec skins you love might feel luckier than getting 1 Covert you dislike, even though statistically the Covert is more valuable. The tool measures probability deviation, not personal satisfaction.
Can I use this to predict future results?
Absolutely not. Each case opening is independent, and past results have zero influence on future outcomes. A luck score of -50 does not mean you're "due" for good luck. This is a retrospective analysis tool only. For more information on this common misconception, see our guide on the gambler's fallacy.
What's a "normal" luck score range?
Most players with reasonable sample sizes (100+ cases) will have luck scores between -30 and +30. Scores beyond -50 or +50 are statistically unusual but not impossible. Extreme scores (-75 or +75 and beyond) represent approximately the top/bottom 1% of all possible outcomes.
Why is my luck score still changing with more cases?
Luck scores reflect cumulative results. As you add more data, the score becomes more stable and reliable. Early on, a single lucky or unlucky outcome can swing your score significantly. With larger sample sizes, individual outcomes have less impact on the overall score.
Does StatTrak affect the luck calculation?
Currently, this tool analyzes rarity tier outcomes only and doesn't separately track StatTrak items. StatTrak has a flat 10% chance on any drop, so it doesn't change your rarity-based luck score. A future version may include StatTrak analysis.
How is the percentile calculated?
The percentile is derived from the cumulative distribution function of your overall z-score. If you're in the 75th percentile, it means approximately 75% of all possible outcomes with your case count would be less lucky than yours. This uses standard normal distribution tables.
Last updated: January 2026