# Chess.com rating vs. USCF/FIDE rating?

• 4 years ago · Quote · #1

In Chess.com there is a bell curve of ratings at http://www.chess.com/echess/players.html. It shows an average of 1384 with almost everyone between 700 and 2100. I imagine that if one took all of the USCF rated players or all the FIDE rated players you would find a similar bell curve, probably with a different average and different extents. Assuming that all of the ratings are roughly bell-shaped then someone could create a mathematical formula for translating one rating into another. For any individual player the formula might produce very incorrect data but when averaged over thousands of players it should be pretty accurate.

So does anyone know if there are published bell curves for USCF/FIDE? Has anyone tried to create a mathematical translation? For those Chess.com players who do have official ratings elsewhere does there seem to be a reasonable correlation between ratings here and ratings elsewhere?

• 4 years ago · Quote · #3

I think USCF has more 0-1000 rated players then Chess.com, making the bell curve wider, or back more.

• 4 years ago · Quote · #4

Ratings are not absolute, they are relative to other people in the same rating pool. As such, it does not make sense to compare ratings from different rating pools. That's even before you get into the issue of correspondence vs. otb play.

• 4 years ago · Quote · #5

Its an interesting question... but the ratings pools may not be equivalent (since otb club players who have more expensive uscf ratings tend to be stronger than casual internet players).  The best way would be to collect a large sample of ratings of people who have both uscf and chess.com ratings.

• 2 years ago · Quote · #6

So there you go.

• 2 years ago · Quote · #7

I guess it also depends on what times we are talking here: i doubt most players at chess.com ever play 2 hour games.Most people play 5 or even 1 minute games.

If USCF has tournaments for 5 minutes only or 1 minute,,then those should be the ratings  to compare.

• 2 years ago · Quote · #8

I'm 959 USCF and 1840 Chess.com, but I don't think that I'm a very representative sample

• 2 years ago · Quote · #9

There is no way to translate them, period.  They are based on completely different systems, and populated by completely different pools of players.

It's about like trying to compare two glasses of juice, sight unseen.  You don't know if either is apple, or orange, or grape, you don't know if they are natural or sweetened, you don't know if they are fresh squeezed or from concentrate, and you don't know the exact size of either glass.

So how do you compare them?

• 2 years ago · Quote · #10
sbowers3 wrote:

For those Chess.com players who do have official ratings elsewhere does there seem to be a reasonable correlation between ratings here and ratings elsewhere?

The correlation is that ratings here are way inflated. I'm rated about 1840 at ASPCC (a tiny CC club with about 100 members, uses USCF rating formula) and I'm rated about 1560 at IECC (email chess club with several hundred active members, I think they also use USCF rating formula). I'm active in all 3 clubs BTW, so my ratings are all up-to-date.

I've had great luck clobbering "B" (+1600) & "A" (+1800) players here and they all seem to be overrated (compared to opponents at ASPCC and IECC), just like I am at 2007.

• 12 months ago · Quote · #11
sbowers3 wrote:

In Chess.com there is a bell curve of ratings at http://www.chess.com/echess/players.html. It shows an average of 1384 with almost everyone between 700 and 2100. I imagine that if one took all of the USCF rated players or all the FIDE rated players you would find a similar bell curve, probably with a different average and different extents. Assuming that all of the ratings are roughly bell-shaped then someone could create a mathematical formula for translating one rating into another. For any individual player the formula might produce very incorrect data but when averaged over thousands of players it should be pretty accurate.

So does anyone know if there are published bell curves for USCF/FIDE? Has anyone tried to create a mathematical translation? For those Chess.com players who do have official ratings elsewhere does there seem to be a reasonable correlation between ratings here and ratings elsewhere?

Thanks for that link of the bell curve and other statistics. Comparing my stats for blitz and standard made me feel pretty good.