# Is your actual Elo rank integer-based or decimal-based?

I'm sure that the published rankings are reported rounded to the nearest integer!

But for the purposes of the calculation of the next rankings are the Elo ranks of GMs considered to actually be those integers, or does the managing body track their Elo score to one or more decimal places.

The answer is relevant to my next question (will link after posted)

## 2 Answers

As you can see from Nakamura's rating calculations for the 2022 GCT Saint Louis Rapid and Blitz - Rapid when he lost 47.80 rating points FIDE uses floating point arithmetic for it's calculations rather than integer. This is not because GMs are special it is because it is the obvious common-sense way of doing things and is done for all ratings for all players.

• I doubt they actually use floating point. I'd hope they use fixed-point decimals, since they only need two decimal points (and I think the only reason they even need 2 instead of 1 is because some players used to have K=15.) You'd hate for a 0.4999999 situation to come up and suddenly a player is getting rounded down instead of up at the end of the month.
– D M
Dec 18, 2022 at 3:23

Elo ratings are calculated allowing changes with decimals to occur after each game. However at the end of the month all Elos get rounded to the nearest integer.

Imagine Player A has a rating of 2000 and plays two tournaments this month gaining 7.4 Elo points in each. On January 1st, his rating of 2014.8 will turn into 2015 (and that's the number that will be used in all future calculations)

On the contrary, if the same player with a starting Elo of 2000 played one tournament in December and the other one in January, he'd make it to 2007 by January 1st and then to 2014 by February 1st.