How can someone premove in 0.0 seconds?

This guy was playing super fast on some moves, and it didn't seem like normal premoves. When I looked at the time-stamp after the game (1+0), there was no bar, and it looks like he/she made the move instantaneously, without even using the 0.1 second that a premove would take.

Move 39.

I didn't know you could do this. How do you do it?

I'm sorry kay but I didn't catch it but I am interested in knowing how this is possible. Could I annoy you and ask you to please repeat it? 📌

How do you premove? I've always just moved the piece and held it until my opponent moves and then drop it when they do. Been doing that way for 16 years. Right click or something?

Very well then.

Thanks, NotFx

Many players have lag so there is second or so delay. Someone's time might go 0.00 but still be able to do move or two.

You just need a connection to the chess.com servers with a RTT of below (probably) 50ms and you can replicate this.

The chess.com clock runs in real time and does not take transport times into account, but unless your internet is atrocious you won't be at any significant disadvantage.

All premoves are supposed to take 0.1 seconds. Unless something recently changed.

https://support.chess.com/customer/en/portal/articles/1444864-what-are-premoves-and-how-do-they-work-

Looks like a glitch or bug may have crept into the code, in that game, unless the site did change something.

I once did a premove in 0.0 seconds.  I think the key is to actually not have it be a pre-move; you need to move after your opponent moves, but by less than 0.1 seconds.

If you move before your opponent does, you get a premove with 0.1 seconds.  If you move 0.03 seconds after your opponent moves, I think you get an 0.0 move.

i have seen my opponents run out of time but they get to move still which makes me run out of time

@guineapig25, this would explain what causes that: https://support.chess.com/customer/en/portal/articles/1444849-why-did-the-clock-times-suddenly-change-the-clocks-seem-broken-?b_id=12321 

I guess that is possible. Seems that all moves should count as at least 0.1 if premoves do. 

i do it in tactics

Since you have to fit your move into a window of 0.1 seconds (or maybe 0.05 seconds if they round the time), I'm not particularly concerned about it.  It's not like you'll be able to do it on purpose.

Good Game

?????