Frequently Asked Questions (FAQs)

What are ROI and Profit%?

ROI stands for Return on Investment. It is the average value you can expect to receive when you open a container. For example, if a container costs $10 and has an ROI of 50%, it will return you an average of $5 per container. However, this does not take into account any losses from taxes or other fees when selling the items. Profit% is the chance of opening an item that is more expensive than the cost of the container. For example, if a container costs $10 and has a Profit% of 10%, on average you would need to open 10 containers to get an item worth more than $10. Again, this does not include any losses from taxes or other fees when selling the item.

What is ROI Percents?

ROI Percents is a page that shows the percentage of a container's value contributed by each rarity. It displays all of the rarities and items that can be obtained from a particular container, with the most valuable items at the top of each rarity. The size of each item is based on its average unboxed value, with the most expensive items taking up the most space.

How does the Simulate page work?

The Simulate page is a tool that allows users to simulate unboxing a container and see their chances of receiving a specific item or wear. It also displays the probability of receiving any rarity, item, or StatTrak (a feature that tracks the number of kills made with a weapon). To use the Simulate page, a user can select a container and input the number of times they want to simulate unboxing it. The page will then simulate the chances of receiving each item or wear in the form of a pie chart. The user can also filter the potential items by rarity, wear or StatTrak status to see the chances of receiving specific types of items and simulate the unboxings until you inevitably simulate what you're looking for. The History icon in the top left can be used to view past simulations.

How are the costs of Past Operation rewards calculated?

The cost of items on the Past Operations are based on the cost of $0.45 USD per star when purchased directly from Steam. This cost is used to calculate the value of items that could previously be obtained by redeeming stars, such as special skins or other in-game items.

How are these numbers calculated?

In 2017, when Valve released CS:GO to China, they were forced to publish the odds of their cases, capsules, etc. This official source confirms that each rarity is 5x rarer than the past rarity to receive, except for exceedingly rare special items (knives, gloves) which are 2.5x rarer than the covert rarity, and industrial grade to mil-spec grade which are 4.8x rarer. All items within the same rarity have the same chance to receive.

With this knowledge its possible to calculate how often you'll receive each item, but not how often you receive each wear for each item (field-tested, factory new, etc.).
This in-depth look at float/wear values and how they work by CSGOFloat here is what allows the calculation of wears for each item. Without going into too much detail, each item has a minimum wear and a maximum wear between 0-1, a.k.a a wear range. This directly determines the chance to receive each wear, with a wear range of 0-1 having the corresponding wear chances:

WEAR	PROBABILITY
Factory New (0.00-0.07)	~3%
Minimal Wear (0.07-0.15)	~24%
Field-Tested (0.15-0.38)	~33%
Well-Worn (0.38-0.45)	~24%
Battle-Scarred (0.45-1.00)	~16%

What if the wear range of the item isn't 0-1 though? These probabilities get squished into the wear range of your item. For example, if the wear range of your item is 0-0.5 these are the corresponding probabilities:

WEAR	PROBABILITY
Factory New (0.00-0.07)	~23.57%
Minimal Wear (0.07-0.15)	~24.43%
Field-Tested (0.15-0.38)	~44.89%
Well-Worn (0.38-0.45)	~4.15%
Battle-Scarred (0.45-0.5)	~2.96%

A Factory New (0-0.07 wear) wear in a full wear range item (0-1) has a chance of 3% and a Minimal Wear (0.07-0.15) in a full wear range item (0-1) has a chance of 24%. If you squish this in a 0-0.5 float range, these ranges for wears get shifted from 0-0.07, to 0-0.035 at 3% drop chance and 0.035-0.075 at 24% drop chance, resulting in 3% + (0.07-0.035/0.075-0.035 * 24%) = 24% chance of receiving Factory New.

If you're following along you may be confused at why the table specifies a different result to the calculations, and this is because there is one last factor, missing wear ranges. On a 0-1 wear range item, there are specific floats that cannot be received from unboxing, at the edge of each wear rating. For example, at the edge between Factory New and Minimal Wear (0.07), there is a 0.01 range of wears that are NOT unboxable, meaning you will not unbox an item with a wear value between 0.07-0.08. All the missing wear ranges for a item with a wear range of 0-1 is, 0.07-0.08, 0.15-0.16, 0.38-0.39 and 0.45-0.46. The most logical theory for why these gaps exist is to distinguish the best minimal wear dropped from the worst factory new dropped, as they have to have at least 0.01 difference in wear.

These missing wear ranges are also squished into the wear range of the item, e.g. in a 0-0.5 wear range item, you will not receive an unboxed item with a wear between 0.035-0.04, as in a 0-1 wear range you will not receive an unboxed item with a wear between 0.07-0.08. This means in a 0-0.5 float range, the ranges for wears get shifted from 0-0.07, to 0-0.035 at 3% drop chance and 0.04-0.075 at 24% drop chance, resulting in 3% + (0.07-0.04)/(0.075-0.04) * 24% = 23.57%.

When you can predict how often you receive an item, and how often you will receive each wear of the item you can then combine all values to find an ROI and a Profit% for each container in CS:GO.

Where are prices sourced from?

All prices are sourced from SkinsBook's API, detailed and available here. This API was chosen as it is one of the few available with SkinsBook and Steam pricing for free, although it does offer even more pricing sources, they have not been implemented as of yet, this is something that can be added if there is demand for it.

In extreme situations where a price for steam or SkinsBook is not available, for example, knives over the steam wallet limit of $2000, a SkinsBook to Steam ratio is applied to the item to predict using the other pricing source's value for the item. For example, the Karambit | Crimson Web (Factory New), is a very rare and sought after item with an unbox chance of 1 in 4,868,774 cases that contain it. Hence it will sell on SkinsBook for $3448 (as of writing), which is over the steam wallet limit and is predicted to have a steam value of $4646 (as of writing) due to knives being 1.347 times more expensive on steam than SkinsBook on average.