Methodology
How NerdyScore Rates Rarity
Rarity Scale Overview
What the rating measures
We track the marketplace listings we observe for every game on a platform and compare those totals against one another. A game we've observed in far fewer listings than most of its platform scores high, while one we've observed in abundance scores low.
One thing we decided early on is that a game's rating is relative to its own platform. The question we are trying to answer is how hard is this game to find compared to other games on the same platform? We do not claim that an R8 on one platform and an R8 on another are of equal scarcity. This is the opposite of Fun Factor, where a score means the same thing wherever the game came out.
Ratings are steadier on platforms with plenty of market activity. Systems that sold far fewer games in the first place give us much less to observe, so ratings there are noisier and worth reading with more slack.
What isn't rated yet
Not every title carries a rarity rating, but that does not mean these games will never have one. Our focus to begin with was site-wide rarity values for everything we consider part of a platform's main set, which excludes variants and bundles. A few ratings outside that scope have made it in where we were confident in the outcome, but not many.
Where there is no rating we show none. An unrated title never borrows a rating from the release it is a variant of, and never gets a placeholder number, because either would read as a measurement we have not actually made.
What it is not
This is not a production figure, a print run, or a population census. We do not know how many copies of a game were manufactured or how many survive, and the rating does not claim to.
It is also not a measure of demand or value. A game can be hard to find and inexpensive, or common and expensive, which is why rarity and market value are shown as separate scores.
Ratings are recalculated as new listing data arrives, so a game's rating can move as the market does.
The scale
R1 is the most common tier, R10 the rarest.
We have almost never seen one of these listed. When a copy does surface, it is an event in itself.
We see these rarely enough that you cannot plan around finding one. For collectors chasing a complete set, they are often the titles that make finishing it difficult.
This is a standout scarce title on its platform. We see copies from time to time, but not often enough that the right one is easy to land.
These seldom turn up in normal browsing. We do see copies, but not often enough that you'll have much choice in condition or seller.
These are noticeably harder to find than the typical game on the platform. We see copies often enough, but you're usually choosing from a thin selection rather than a crowded one.
These are harder to track down than the typical game on the platform. It's not a serious hunt, but you won't stumble across one without looking either.
These are findable with a little searching. We see fewer of them than the platform norm, but often enough that tracking one down isn't usually a challenge.
These are fairly easy to find. We see copies listed regularly, and there's usually enough on the market to give you some choice.
These are widely available compared with most games on the platform. We see them listed constantly, so finding a copy takes little effort.
These are among the easiest games to find on the platform. We see them listed daily, in a multitude of conditions, well above the platform norm.