Stockfish 12

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Joost VandeVondele

Sep 2, 2020, 10:29:07 AM9/2/20
to FishCooking
It is our pleasure to release Stockfish 12 to users world-wide

Downloads will be freely available at

This version 12 of Stockfish plays significantly stronger than
any of its predecessors. In a match against Stockfish 11,
Stockfish 12 will typically win at least ten times more game pairs
than it loses.

This jump in strength, visible in regular progression tests during
development[1], results from the introduction of an efficiently
updatable neural network (NNUE) for the evaluation in Stockfish[2],
and associated tuning of the engine as a whole. The concept of the
NNUE evaluation was first introduced in shogi, and ported to
Stockfish afterward. Stockfish remains a CPU-only engine, since the
NNUE networks can be very efficiently evaluated on CPUs. The
recommended parameters of the NNUE network are embedded in
distributed binaries, and Stockfish will use NNUE by default.

Both the NNUE and the classical evaluations are available, and
can be used to assign values to positions that are later used in
alpha-beta (PVS) search to find the best move. The classical
evaluation computes this value as a function of various chess
concepts, handcrafted by experts, tested and tuned using fishtest.
The NNUE evaluation computes this value with a neural network based
on basic inputs. The network is optimized and trained on the
evaluations of millions of positions.

The Stockfish project builds on a thriving community of enthusiasts
that contribute their expertise, time, and resources to build a free
and open source chess engine that is robust, widely available, and
very strong. We invite chess fans to join the fishtest testing
framework and programmers to contribute on github[3].

Stay safe and enjoy chess!

The Stockfish team


Rob Ovenden

Sep 2, 2020, 10:43:36 AM9/2/20
to FishCooking
Sent early? Don't see anything anywhere, nothing at abrok site.

Jothi Lingam

Sep 2, 2020, 10:51:21 AM9/2/20
to FishCooking
Congratulations to SF team!! and great work.....

Sep 2, 2020, 11:12:56 AM9/2/20
to FishCooking
Message has been deleted

Andy Erly

Sep 2, 2020, 11:14:48 AM9/2/20
to FishCooking
Hmm, maybe the wording on the page could use some improvement... 

"What you're getting: just the Stockfish engine. You will need to use your own UCI-compatible chess program."

^ If I didn't know anything, I'd not know what UCI meant, and be confused why I needed a chess program (isn't that what Stockfish is?).

Who do I talk to about this?


Sep 2, 2020, 2:17:54 PM9/2/20
to FishCooking
Hey no computer expert here so got a question: Once I download SF12 and install it on my UCI (Arena 3.5.1) is that it? Or do I need additional steps to "activate" the NNUE function to get the most out of it during tournament play? Thanks.

Andy Erly

Sep 2, 2020, 2:21:14 PM9/2/20
to FishCooking
Hey! They improved the download page already. Well done to whoever that was.

@ani19bd NNUE is activated by default. If it's running and you haven't touched anything, it's using the NNUE.


Sep 2, 2020, 2:27:13 PM9/2/20
to FishCooking
@Andy Erly, ok thanks. Was a bit confused because in a different blog SF team recommended to download the "*.nnue" file and place it in the same directory as the binary file. So I guess I don't need to do that. (

Sep 2, 2020, 2:46:18 PM9/2/20
to FishCooking
ani19bd — Sorry, I didn't get around to updating the blog yet. Just fixed it:

Andy Erly — Thanks :) Delay was because of morning meetings…

Sep 2, 2020, 3:11:44 PM9/2/20
to FishCooking
We did it :)

Jose Stefan

Sep 2, 2020, 3:56:34 PM9/2/20
to FishCooking
I'm having a problem with this release and hash sizes while using Arena Chess 3.5.1

I'm testing a match between SF12 vs SF11. My hash is set as 1024 MB on the global UCI options. Works find with SF11, but SF12 reports 66 mb being used.

If i go to window's task manager, sf11 is using around 1gb of ram as expected, while sf12, is not respecting my choice and using 43 MB.

If I open the Engine Log window on arena chess, and re-start the engine, I can see the hash command is actually set, but doesn't seem to affect the process size:

2020-09-02 15:51:30.921-->1:uci
2020-09-02 15:51:30.977<--1:id name Stockfish 12
2020-09-02 15:51:30.977<--1:id author the Stockfish developers (see AUTHORS file)
2020-09-02 15:51:30.977<--1:option name Hash type spin default 16 min 1 max 33554432
2020-09-02 15:51:30.978<--1:uciok
2020-09-02 15:51:30.979-->1:setoption name Hash value 1024
2020-09-02 15:51:30.986*1*Child Process Prio Adj:  PID 10932 conhost.exe
2020-09-02 15:51:30.986<--1:info string Hash table allocation: Windows large pages used.
2020-09-02 15:51:30.987-->1:isready
2020-09-02 15:51:31.050<--1:readyok

Does it have something to do with the message:
"Hash table allocation: Windows large pages used."

If so, what process is supposed to be taking the memory? I'm sorting the process list by size and nothing comes close to how SF11 worked.

On Wednesday, September 2, 2020 at 10:29:07 AM UTC-4 Joost VandeVondele wrote:

Tomasz Sobczyk

Sep 3, 2020, 6:07:52 AM9/3/20
to FishCooking
Hash initialization is now lazy so you need to start analysis for the hash pages to be claimed by the process.

Michael Leahy

Sep 4, 2020, 12:43:16 PM9/4/20
to FishCooking
Congratulations on Stockfish 12.

I tried using it in Chess Openings Wizard and Apple says, " The executable does not have the hardened runtime enabled."

It also appears to not be code signed. I can add a code signature but..

How can I get a version compiled with the hardened runtime enabled?

On Wednesday, September 2, 2020 at 10:29:07 AM UTC-4 Joost VandeVondele wrote:


Sep 4, 2020, 1:02:33 PM9/4/20
to FishCooking
+130 Elo is incredible! This is the largest growth I've seen in some time. It is especially incredible considering the strength at which SF11 plays at.


Sep 4, 2020, 1:25:29 PM9/4/20
to FishCooking
Hey can't install on Arena 3.5.1 message displayed: "Hash table allocation : Windows large page not used"
All other previous version SF runs perfectly fine.

Joost VandeVondele

Sep 4, 2020, 1:32:15 PM9/4/20
to FishCooking
'Hash table allocation : Windows large page not used' is just for information. Not an error, and hardly a warning.

It gives a hint about an 'expert feature' that is described here


Sep 7, 2020, 2:26:00 PM9/7/20
to FishCooking
As usual, if anyone has old hardware, he can use Cfish. It is faster, especially on x86-64 SSE2-only CPUs (up to 30% faster than Stockfish has been reported for those). Cfish also MIGHT heat your CPU less, because it uses less vector instructions. (but this was not tested).

пятница, 4 сентября 2020 г. в 20:32:15 UTC+3, Joost VandeVondele:
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