user61433: Blockchain miners calculate the hash of (block data + nonce value). They actually guess (are looking for) nonce in order to get hash staring with a defined number zeroes. (The number of required starting zeros in hash value define the difficulty of finding a nonce that fits - proof of work).
My question is do all miners guess/try nonces from the same pool or range (this way they actually non-efficiently test the same guesses many times) or they somehow split the pool of possible nonces among themselves in order not to try the same nonces multiple times?

user61332: The nonce value is indeed "guessed" by the miner. 
The miner can also choose a part of the coinbase transaction (what the stratum protocol calls the ExtraNonce2). Another part of the coinbase transaction is imposed by the pool: this is the ExtraNonce1, in terms of the stratum protocol.
Pools are supposed to assign distinct ExtraNonce1 to all miners, to prevent duplication of work.

61433: <p>Blockchain miners calculate the hash of (block data + nonce value). They actually guess (are looking for) nonce in order to get hash staring with a defined number zeroes. (The number of required starting zeros in hash value define the difficulty of finding a nonce that fits - proof of work).</p>

<p>My question is do all miners guess/try nonces from the same pool or range (this way they actually non-efficiently test the same guesses many times) or they somehow split the pool of possible nonces among themselves in order not to try the same nonces multiple times?</p>
 61332: <p>The nonce value is indeed "guessed" by the miner. </p>

<p>The miner can also choose a part of the coinbase transaction (what the <a href="https://slushpool.com/help/manual/stratum-protocol/" rel="nofollow noreferrer">stratum protocol</a> calls the <code>ExtraNonce2</code>). Another part of the coinbase transaction is imposed by the pool: this is the <code>ExtraNonce1</code>, in terms of the stratum protocol.</p>

<p>Pools are supposed to assign distinct <code>ExtraNonce1</code> to all miners, to prevent duplication of work.</p>
