FIDE vs Lichess Rating

I always wondered how the Lichess rating compared to USCF/FIDE rating. Especially since the FIDE rating is based on the older Elo rating system and the Lichess rating is based on the newer Glicko-2 system.

Here's what the normal distribution, bell shaped curve looks like for Lichess users playing Classical (standard) games. This curve is from the past week:

Since I don't have a rating, Lichess assigned me a provisional rating of 1500. Looks like the average rating is 1550 for Classical play. If I have a 1700 rating, the curve says that I play better than 68% of Lichess Classical players (at least for last week).

Here's a link to the weekly rating distribution: Rating Distribution

What I always wondered however, was how the Lichess online rating compares with the USCF/FIDE over-the -board (OTB) rating? Particularly for Classical (standard) play since that's what I play on Lichess.

Here's a FIDE vs. Lichess comparison that someone put together. I forget the source. If/when I find it again, I'll post it here. I added the red lines and green lines. I'm assuming the relationship is linear (simple linear regression red line) which I'm sure in real life it probably isn't. My guess is that the delta between the two ratings is lower the higher the rating and vice versa. You can see that a 1750 Lichess player rating is equivalent to a 1500 FIDE rating. I believe the author said the delta was 200, instead of 250 shown here.

What I don't understand are the outliers, far from the linear regression line. How can someone with a 1500 Classical rating from Lichess have a reported 3000 FIDE Classical rating? Besides, the highest FIDE rating is Magnus Carlsen and his FIDE rating is only 2859. I say only, ha.

I had always heard that the Lichess ratings were 'overinflated' compared to USCF/FIDE ratings. But, I just didn't know by how much. Even this comparison is only an estimate with medium probability since the sample size is small. Plus, there are so many variables so it's hard to really compare. I can safely say, however, that USCF/FIDE ratings will be lower than Lichess ratings. How much lower, I have no clue. If I had to make an educated guess, I'd say anywhere from 100-300 which is a pretty big range.

If you want to compare your rating to someone else's, just make sure you compare Lichess ratings to Lichess ratings, and USCF/FIDE ratings to USCF/FIDE ratings. And, if you want a more accurate comparison, ensure the sample size (games played) is similar. Don't compare your Lichess Classical rating based on 12 games to someone else's Lichess Classical rating based on 1,200 games. And, make sure the games played are recent, not from 10 yrs. ago.

Elo ratings:

Scholastic Grade 1= 100 (beginner)
Scholastic Grade 2= 200 (beginner)
Scholastic Grade 3= 300 (beginner)
Scholastic Grade 4= 400 (beginner)
Scholastic Grade 5= 500 (beginner)
Scholastic Grade 6= 600 (beginner)
Scholastic Grade 7= 700 (beginner)
Scholastic Grade 8= 800 (beginner)
Beginner Adult= 800-999
Intermediate= 1000- 1149
Casual Player= 1150-1299
Advanced Player= 1300-1449
Experienced Player= 1500- 1599
Average Club Player= 1600-1749
Strong Club Player= 1750-1899
Tournament Player= 1900- 1999
Expert/ National Candidate Master (NCM)= 2000-2199
National Master (NM)= 2200-2299
FIDE Master (FM)= 2300-2399
International Master (IM)= 2400-2499
Grandmaster (GM)= 2500-2699
Super Grandmaster (SGM)= >2700