Have you ever played a Grandmaster ?

I've

1. Won against penguin gm on lichess.org ultrabullet (He berserked and I flagged him)

2. Lost in 30 moves vs NM otb

I've played the Swedish GM Thomas 'The Hitman' Ernst three times, two losses in tournaments, and a draw in a simul. A dreadful loss to GM Simon Williams (one of those games which makes you feel completely useless). Apart from that I've drawn with with the Croatian GM Vladimir Kovavecic in a tournament in Pula. He's famous for having defeated Bobby Fischer at the Rovinj/Zagreb Tournament in 1970. Furthermore, I drew with GM Daniel Gormally in the 4NCL (the British national chess league), in that game I overlooked a win. He's famous for having tried to punch Levon Aronian's lights out at the Turin Olympiad in 2006. In addition to this I've defeated two IMs, but that doesn't count in this thread!

No, I'm not titled. My peak Elo was 2140 fixed (2167 'live'). My current Elo is E2042. My highest national rating was ECF 199 (the English Chess Federation grading system), which at the time converted to E2250, if I remember correctly.

One of the big differences between titled players and the rest of us is that, although we may on the odd occasion grab a draw or a win against them (when we play great, and they not so great), we're just as likely to drop draws and losses against players who are much weaker than us. About a year before I drew with Kovacevic, I conceded a draw against an E1200 player, and I was never even close to winning that game. Compared to the titled players we have considerable gaps in our chess knowledge/culture which sometimes show us up in a very unflattering light. This is why I advocate going over material that is actually aimed below our level from time to time. Simply put, we need to plug those knowledge gaps, not just stretch ourselves with more advanced material.

Played Tal in a simul in 1988 at the World Chess Festival in Saint John. I drew.

I don't know exactly where the rating limit goes for an NM - am I right in thinking it's a US title? In the United Kingdom, I was considered a strong 'county' player, which means a player strong enough to get on a county's first team. (We did win the national county final once. One of my team mates in that final was none other than Demis Hassabis of Deep Mind and Alpha Zero fame.)

Great achievement!

I've played against GM Simon Williams in Simuls 3 times. I've lost twice and won once. The win was probably the highlight of my chess life. He was very gracious in both victory and defeat.

no

Totally agree. Simon is a very nice guy. I lost horribly to him, but it was still a great post-mortem.

I played GM Gufeld in a Simul. I lost after 25 moves. I felt I played Fritz 5 in the flesh.

Sure, say about 30x times. Some draws (highest was GM Sakaev, former world Top30) or some blitz wins. Everything otb.

I've played Nigel Short when I was very young and not very skilled. And I have also played Bu Xiangzhi. This was more recent... I was actually up in exchange in a fairly even game, thought I saw a tactic, and then he countered it with an incredible mating net. Great guy after the game though, even told me he was worried about the game at one point!

There's quite a big difference between Elo and online ratings.

I played a grandmaster better than Magnus- the computer on level 10.

No. But I have played Masters in USCF competitions. I drew 2 and lost twice to another guy 2 years apart.

No i haven't played a GM.

But I Defeated 

5 IM

2 WGM

5 WFM

15 FM

28 NM 

4 CM