Longest Unbeaten streak?

Do you mean, something like this?

https://www.chess.com/news/view/ding-liren-breaks-mikhail-tals-95-game-undefeated-streak

And so it comes to an end... Ding "The Great Wall of China" Liren was finally broken, by ze french cannon MVL. He still marked his legendary streak with a century:

• 110: Sergey Tiviakov
• 100: Ding Liren
  
• 95: Mikhail Tal
• 93: Vladimir Malakhov
• 86: Mikhail Tal
• 85: Wang Yue
• 84: Milan Drasko
• 82: Vladimir Kramnik

Bogdan Lalic tells me his streak is 157 games, although some were rated only on a national level.

I have had several +200 game winning streaks. Not unbeaten, but winning streaks. They were played against friends who happened to be fish, and so those streaks rightly aren't counted. I have a +150 game winning streak here on chess.com. Again, that's not what we're talking about.

The criteria that matters is FIDE rated classical chess games. Tiviakov's 110 game streak remains the longest on record, but with an asterisk. Ding's is the longest where he faced top competition though. Tiviakov admits that many of his opponents weren't of a particularly high quality (some who weren't master strength), especially compared to Ding's list. But then, a close look at Capa's unbeaten streak would also show that many of his customers weren't master strength by today's standards. 

Ding's record of 100 straight undefeated against master strength opposition in organized classical chess compares favorably with Tal's record. 

Here's a link to the story in Chessbase:

https://en.chessbase.com/post/ding-defeated

Ding Liren deserves the record if he hasn't officially got it. Although mostly he "just" drew against top competition. I don't regard him as one of the all-time greats despite his unfathomable streak - if you just try not to make mistakes you won't lose often...but you'll also mostly not win many big tournaments and you'll never be world champion.

It's now Carlsen.

Man, ahedresnak beat me to it!!! Yeah, Magnus just took the crown, and I love how earlier, im pfren said that Carlsen couldn't do it, because he plays against high level competition. I'm not dissing im pfren though... im pfren was RIGHT to say that back in 2013... who would have imagined Magnus pulling this off?!?!?!? Unbelievable!!!!!

not if you count Bogdan Lalic's 157 game streak...

Congrats to GM Magnus Carlsen for this big achievement. However, don´t celebrate too much, Magnus, I will take the record soon

Only for longest uneaten steak

How many of 111 games were vs a player with a title?
And how many for Tiviakov streak?
And how many for Lalic?

I still can't believe that he made an 111 games streak against 2700+ opposition- this is supernatural.

Carlsen's weakest opponent was a FM, rated 2311.

Another FM at 2365, and the rest 109 were top notch.

Carlsen mentioned something like 109 games vs elite opposition

Tiviakov = 110 but weaker opponents

Lalic i don't know

Back when Ding came to the end of his streak, Bogdan Lalic sent me a database with his games, total of 157 in it with his own annotations. I've stripped out the annotation for publishing here.

Speaking with him tonight, he now says it's 163 games, and has sent me a database of those games, but i don't have time tonight to compare them side-by-side.

Lalic's streak is often discounted because he was not playing against elite players, or because there are many short draws, but he might well argue that he has no control over who his opposition is (mainly open tournaments, open to anyone to play) and that his opponents are not obliged to accept draw offers, if indeed the offer was made by Lalic.

Looking at twitter tonight, Jonathan Tisdall amongst others state that Lalic's record is "unverifiable", but i'm not sure that's true. AIUI, not all of Lalic's games were played in FIDE-rated events, but the ones which were should certainly be recorded with them. The English Chess Federation (ECF) should have record of the other games and the other national federations whose jurisdiction games were played should also have records where game were played there.

As for actual verification, well, surely only Guinness World Records should be the arbiter of such an event, of course they would need to speak first to all the federations involved...

Saving the rare moment where @pfren fanboys for posterity!

”Lalic's streak is often discounted because he was not playing against elite players”

Not exactly elite, no, they had an average rating in the 2200s :-)

I agree completely with @pfren. What Magnus is doing is unprecedented (hence the record). And to do it against such competition makes it feel supernatural. 

Also the fact that Lalic dropped a lot on the rating list after all those short draws against much lower rated opponents says a bit about how serious that alleged streak was, more than 50 of the games were drawn in less than 20 moves.

Games played is certainly the great measuring stick. People always cite Capablanca's 8 12 months duration of 'invincibility', but he did not honestly play as many video games as Tal's 1 12 months span of domination.