CS2 Case vs Buy Calculator

Compare the expected cost of opening cases to get a specific skin versus buying it directly from the Steam Market. Make data-driven decisions and understand the true economics of case opening.

Last Updated: January 2026

Case vs Buy Comparison Tool

Select the rarity of the skin you want, enter the current prices, and see which option is more economical.

Step 1: Select Target Skin Rarity

What rarity tier is the skin you want? This determines the drop probability.

Mil-Spec 79.92%
Restricted 15.98%
Classified 3.20%
Covert 0.64%
Knife/Gloves 0.26%
Note: The odds shown are for getting any skin of that rarity. If you want a specific skin, enable "Specific Skin Mode" below to divide by the number of skins in that tier.

Step 2: Enter Prices

Quick Case Presets: Click to auto-fill common case costs.
$
Current Steam Market price for the case
$
In-game key price ($2.49 standard)
$
Current Steam Market price for the skin you want
Number of skins at this rarity in the case (1 for "any skin")
Enable if you want a specific skin (not just any skin of that rarity). This divides odds by the number of skins in the tier.

Comparison Results

🎰 Opening Cases

$0.00

0 cases expected at $0.00 each

Not Recommended

🛒 Direct Purchase

$0.00

Buy directly from Steam Market

Recommended

💡 Verdict

Loading analysis...

Expected Cases Needed
0
Drop Probability
0%
Cost Difference
$0.00
Savings %
0%

Cost Comparison Visual

Case Opening:
$0
Direct Buy:
$0
💡 Pro Tip: Always compare prices before making a decision.

Probability Context

Understanding the Math: The expected number of cases is calculated as 1 ÷ probability. However, this is an average. Due to variance, about 63% of players will need more than the expected number of cases to get their desired item. See our Streak Calculator for more on variance.

Understanding Case Opening vs Direct Purchase

The Economics of Skin Acquisition

When you want a specific CS2 skin, you have two main options: open cases hoping to get it, or buy it directly from the Steam Community Market. Understanding the economics behind each option is crucial for making informed decisions.

According to probability theory fundamentals from Britannica, the expected value calculation helps determine the average outcome over many trials. For case opening, this means understanding how many cases you'd need to open on average to get a specific skin.

How Case Opening Probability Works

Valve officially disclosed CS2 case drop rates in accordance with transparency requirements. The probability tiers are fixed:

Rarity Tier Drop Chance 1 in X Expected Cases
Mil-Spec (Blue) 79.92% 1 in 1.25 ~1.25 cases
Restricted (Purple) 15.98% 1 in 6.26 ~6 cases
Classified (Pink) 3.20% 1 in 31.25 ~31 cases
Covert (Red) 0.64% 1 in 156.25 ~156 cases
Rare Special (Gold) 0.26% 1 in 385 ~385 cases

The "Specific Skin" Factor

The odds above are for getting any skin of that rarity tier. If you want a specific skin (like a particular AWP skin rather than just any Covert), you need to divide the odds by the number of skins in that tier.

For example, if a case has 17 Mil-Spec skins and you want a specific one:

  • Any Mil-Spec: 79.92% chance per case
  • Specific Mil-Spec (1 of 17): 79.92% ÷ 17 = 4.7% chance per case
  • Expected cases for specific skin: ~21 cases instead of ~1.25

Why Direct Purchase Usually Wins

Research published by the National Center for Biotechnology Information (NCBI) has studied loot box mechanics and their economic implications. Key findings include:

  • Negative Expected Value: Cases are designed with negative expected value, meaning you statistically lose money over time
  • Variance is High: You might get lucky or unlucky, but most players lose
  • Psychological Factors: The excitement of opening cases can lead to overspending
  • Direct Purchase is Predictable: You know exactly what you get and what you pay

When Case Opening Might Make Sense

While direct purchase is usually more economical, there are scenarios where case opening might be considered:

  • Entertainment Value: If you enjoy the opening experience and have a strict budget for entertainment
  • Any Skin Will Do: If you're happy with any drop from the case, not a specific skin
  • Investment Cases: Rare/discontinued cases where even common drops have value
  • Low-Value Targets: Very cheap Mil-Spec skins where opening 1-2 cases is comparable to market price
Important Reminder: Case opening is a form of gambling with real money. Always set a strict budget you can afford to lose, and never chase losses. If you're struggling with gambling urges, visit BeGambleAware for support.

Understanding Variance

Expected value tells you the average outcome, but real-world results vary significantly. According to probability mathematics from Wolfram MathWorld, case opening follows a geometric distribution.

Key variance facts:

  • 50% of players will need more than the expected number of cases
  • About 37% of players (1 - 1/e) won't get the item after the expected number of cases
  • To have 90% confidence of getting a specific item, you need about 2.3× the expected cases
  • Some players get lucky early, but many experience long "dry streaks"

Related Tools

Use these tools alongside the Case vs Buy Calculator to make informed decisions:

Frequently Asked Questions

How accurate is this calculator?

The probability calculations use Valve's officially disclosed drop rates, which are 100% accurate. The expected cost calculation is mathematically precise based on probability theory. However, actual results will vary significantly due to randomness - you might spend more or less than the expected amount.

What does "Expected Cases Needed" mean?

This is the average number of cases you'd need to open to get one drop of the target rarity. It's calculated as 1 ÷ probability. For example, with a 1% drop rate, the expected cases needed is 1 ÷ 0.01 = 100 cases. About half of players will need more than this, and half will need less.

Why is direct purchase almost always cheaper?

Cases have negative expected value by design. Valve profits from both case/key sales and market fees. The house always has an edge, similar to casino games. Direct purchase removes the gambling element and gives you exactly what you pay for.

Should I use "Specific Skin Mode" or not?

Use "Specific Skin Mode" if you want one particular skin (e.g., "I want the AWP Asiimov specifically"). Leave it off if you're happy with any skin of that rarity (e.g., "I want any Covert from this case"). The mode significantly changes the expected cost calculation.

What about StatTrak versions?

StatTrak has an independent 10% chance on any drop. If you want a specific StatTrak skin, the odds are already low for the skin × 0.10 for StatTrak. For most StatTrak skins, direct purchase is even more favorable compared to case opening.

Does this account for selling other drops?

No, this is a simplified comparison. In reality, you'd receive other drops while trying for your target. Those drops have value (minus 15% Steam fees), partially offsetting your costs. See our Case ROI Calculator for a more complete expected value analysis.

How do I find the number of skins in each tier?

Check the case on the Steam Market or use community resources like CSGOStash. Most cases have around 17 Mil-Spec, 5 Restricted, 3 Classified, 2 Covert, and a pool of rare special items. The exact numbers vary by case.

What if I get lucky and get the skin in one case?

That's possible! The calculator shows expected/average outcomes, not guaranteed results. Some players get their desired skin on the first try. But for every lucky player, there are many who needed far more cases than expected. Don't count on getting lucky.

Disclaimer: This calculator is for educational purposes only. Case opening involves financial risk and is a form of gambling. Only open cases with money you can afford to lose. Never chase losses. If you're under 18, do not open cases. For gambling support, visit BeGambleAware.

Last updated: January 2026