user15874: I've watched a couple of games where people play against stockfish level 8 on lichess, and they pretty much lose all the time. Is it possible for someone to beat a level 8 computer in any time between 3+0 and 15+0?

user19107: Yes, it is possibile and not so unlikely under two conditions:

the human is quite strong
lichess is browsed via mobile (not on a desktop pc) 

Please note that the elaboration is not done serverside, but clientside.
That means that it uses (part of) the resources of the hardware you are using when browsing lichess (!).
In other terms if you browse on a mobile the engine will be weaker.
Just today I drew a fast game (I’m near 2300 elo and I run it on a Samsung S8 hw).

user16788: IMHO playing against Stockfish level eight is a lost cause when playing against its full 16 quad core processors and basically unlimited flash storage, no matter the time constraints. Magnus Carlson stated a couple of years ago that he always lost against that computer program. The lichess version is but a shadow of its real self.

user12873: Assuming Stockfish level 8 is full strength Stockfish, it's possible to beat it but extremely unlikely.
In very rare cases, Stockfish will incorrectly evaluate a complicated position, unless given a minute or two to think. If a human were to get in such a position in a 3 0 game, Stockfish could make a fatal blunder.
However, the chances of the human making a mistake first is far greater.
Making the time control longer than 3 0 favors Stockfish, since it has more time to think if it's misevaluating something.
If Stockfish level 8 is only 2200-2400 (I've read this on some online sources), then beating it is more realistic.

15874: <p>I've watched a couple of games where people play against stockfish level 8 on lichess, and they pretty much lose all the time. Is it possible for someone to beat a level 8 computer in any time between 3+0 and 15+0?</p>
 19107: <p>Yes, it is possibile and not so unlikely under two conditions:</p>

<ol>
<li>the human is quite strong</li>
<li>lichess is browsed via mobile (not on a desktop pc) </li>
</ol>

<p>Please note that the elaboration is not done serverside, but clientside.
That means that it uses (part of) the resources of the hardware you are using when browsing lichess (!).</p>

<p>In other terms if you browse on a mobile the engine will be weaker.</p>

<p>Just today I drew a fast game (I’m near 2300 elo and I run it on a Samsung S8 hw).</p>
 16788: <p>IMHO playing against Stockfish level eight is a lost cause when playing against its full 16 quad core processors and basically unlimited flash storage, no matter the time constraints. Magnus Carlson stated a couple of years ago that he always lost against that computer program. The lichess version is but a shadow of its real self.</p>
 12873: <p>Assuming Stockfish level 8 is full strength Stockfish, it's <em>possible</em> to beat it but <em>extremely unlikely</em>.</p>

<p>In very rare cases, Stockfish will incorrectly evaluate a complicated position, unless given a minute or two to think. If a human were to get in such a position in a 3 0 game, Stockfish could make a fatal blunder.</p>

<p>However, the chances of the human making a mistake first is far greater.</p>

<p>Making the time control longer than 3 0 favors Stockfish, since it has more time to think if it's misevaluating something.</p>

<p>If Stockfish level 8 is only 2200-2400 (I've read this on some online sources), then beating it is more realistic.</p>
