Board Game Arena

Hi,

I am failing to understand how ELO is calculated. I have read the topic about it, but it seems like something is missing.

I have beaten someone with a 185 rating and it gave me +12.

4 games later, I have won a 4 player game and it gives me +14 for beating 3 people of 436, 284 and 241.

My ELO was not significantly changed between the games. I was surprised to receive only +14.

Is it prorated for the number of player?

Thanks

Yes, there's some factor that has to do with the number of players, but I believe it depends on the game. Anyway, if you hover on your elo score, you can see some details of the calculations:

https://boardgamearena.com/table?table=630255333 (win prob. 38% -> +12.47)
https://boardgamearena.com/table?table=652148387 (win prob. 35% -> +4.35, so approx 1/3 because there are 3 opponents instead of 1)

Maxime Vigneault wrote: ↑15 April 2025, 19:13 Hi,

I am failing to understand how ELO is calculated. I have read the topic about it, but it seems like something is missing.

I have beaten someone with a 185 rating and it gave me +12.

4 games later, I have won a 4 player game and it gives me +14 for beating 3 people of 436, 284 and 241.

My ELO was not significantly changed between the games. I was surprised to receive only +14.

Is it prorated for the number of player?

Thanks

Your ELO is calculated as if you'd played every other player in the game head-to-head. The FAQ also says "the K factor is adjusted depending on the total number of players to make sure ELO variation is not too important (or too unimportant)," but it doesn't actually say how it is adjusted.

Another possible factor is that between the first game you described and the second you moved into a different K-factor tier. If you moved from a K-factor of 40 to 20, it would make a noticeable difference even if your ELO remained exactly the same. But looking at your history you are way past your 21st time playing this game, so that doesn't explain it in this case.

For questions like this, it is useful to provide links to the games because there is more information available on the game results page than you have in your post.

Jellby wrote: ↑15 April 2025, 19:19 Yes, there's some factor that has to do with the number of players, but I believe it depends on the game. Anyway, if you hover on your elo score, you can see some details of the calculations:

https://boardgamearena.com/table?table=630255333 (win prob. 38% -> +12.47)
https://boardgamearena.com/table?table=652148387 (win prob. 35% -> +4.35, so approx 1/3 because there are 3 opponents instead of 1)

That would make sense. Thanks a lot