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Questions tagged [difficulty]

This tag should be used for questions regarding difficulty which encodes the likelihood of one hash to succeed at mining a block. Indirectly, it is a measure of the total hashing power of all miners for a given cryptocurrency.

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Which is the better estimator for future mining intervals, the 10 minute protocol target or the observed, historical average?

The Bitcoin protocol is designed so that the network difficulty is periodically adjusted so that new blocks are mined on average every 10th minute. However, looking back the last 10 years, it appears ...
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Is the bits field a unique representation of the target?

The bits field is the compact representation of the target. Example: bits: 1d00ffff target: 00ffff0000000000000000000000000000000000000000000000000000 bits: 1cfff00 target: ...
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Mining Difficulty and Leading Zeros

I understand that the Bitcoin mining problem is to find a string s (hash of previous block + Merkle Tree Hash + nonce) such that sha256(s) has n leading zeros, where n determines the mining difficulty....
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How difficult is it to confirm a Bitcoin Block?

If I have done the math right to come up with this hash, to confirm a true block and this is a confirmed hash. You can look it up here Bitcoin Block #570240 ...
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bitcoin difficulty determination

Given the bitcoin difficulty information in https://bitcoinwisdom.com/bitcoin/difficulty, determine the bitcoin difficulty on April 1, 2019 and April 1, 2020. State any assumptions made in this ...
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39 views

How to calculate difficulty re target?

I am trying to re-calculate difficulty and verify by using the formula T${new}$ = T${old} \times \frac{Time~ taken~ for~ previous~ 2016~ blocks}{2016~\times ~600}$ I used block #s 564697 and 562681 ...
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where in the source code is the the proof of work checking the blockheader hash and nonce?

Where in the source code do we check whether hash(blockheader*nonce) < Difficulty In fact, the line I found is as follows: https://github.com/bitcoin/bitcoin/blob/v0.17.0.1/src/pow.cpp#L87 My ...
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bitcoin's PoW, real time of creating one block

i learn that bitcoin is created every 10 minutes and if block is created faster than 10 minutes, Difficulty will increase. and study deeper, mining process is finding nonce that start 0 to increase 1 ...
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mining difficulty is not changed on regtest

I want to see the automated mining difficulty change on regtest but it did not change even I generated 2016 blocks. How can I see it? // initial difficulty $ ./bitcoinA/src/bitcoin-cli -rpcuser=...
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Mining: what is the lowest possible target? Could it be a block hash of all zeros?

I had a basic question about Bitcoin mining. I understand that as the bitcoin difficulty adjustment becomes harder the hash output will require more 0s in the beginning of the hash. Is it ...
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Difficulty Adjustment Compairson

Thinking about different difficulty adjustments for protecting new coins against attacks from big miners. 2017 when BCH forked from BTC, BCH added the EDA (emergency difficulty adjustment) and updated ...
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where is the adjustment calculation for the target value in the source code?

Can someone point me to the source code and explain how the average is calculated for the adjustment of difficulty that takes place every 2016 ? Update: i have consulted with previous questions but ...
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41 views

Why is Target < Blockhash?

I am currently trying to validate a blocks hash against its target in python3: This is a block in the Blockcypher testnet, and I am using this formula from the Bitcoin Wiki. block_hash = '...
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Why are block header bits necessary? (Valid difficulty is already implied by chain history)

Difficulty or target is implied by chain history, so why does it need to be explicit in the header? I suppose it exposes miner-intended-difficulty, but I don't see why that would be relevant without ...
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is the proof-of-work for safety or efficiency?

i am reading the proof-of-work (aka: pow, target threshold, difficulty, etc.); my understanding is that pow adds a requirement to validate block headers, so that both benign and malign nodes need a ...
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42 views

How does difficulty impact profitability? what is the formula?

I have an Antminer S9 ASIC miner , and I have visited this , but I want to know how difficulty may impact my profitability in the future. I would also like to estimate break even costs.
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Estimated number of hashes

This is not a duplicate of previous, similar questions I've read on StackExchange, since none of those questions, nor the answers, go into the difficulty theory, as espoused on the Bitcoin Wiki. ...
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What needs to be done inorder to change difficulty?

I'm trying for a while to reduce difficulty of main network to do some experiments on transactions and maybe simulate some possible attacks.I came up to change nBits field in chainparams.cpp but it ...
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Why can I observe three different network difficulties in a span of a few days?

https://www.blockchain.com/charts/difficulty If I study the difficulty changes the last 6 months, I can see, as would be expected, that roughly every two weeks, the network makes an appropriate ...
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When update mining difficulty, Is the timespan of the past 2016 blocks approximated value?

I know how to calculate difficulty, and I know it is increased or decreased by checking the timespan of the past 2016 blocks. and I found actual code for calculating timespan: https://github.com/...
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Have all hashes of unlocked difficulty levels of cryptocurrencies been mined?

I'm wondering if all the hashes of a previously unlocked difficulty level of a cryptocurrency, such as 0000000000000000xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx BTC , have been completely ...
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37 views

Mining a new block

Hypothetically, if you only have one node mining in the network, how much time does it take to solve for the nonce assuming for example the current difficulty?
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How to calculate coins mined per day?

Sorry for the noob question I'm pretty new to crypto coins and all this stuff. :) I wonder why the formula <your hashrate> / <coin difficulty> gives the mined coins as a result...Formula ...
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How is the target in Bitcoin set? Who does this?

I want to understand how the target value is adjusted or by whom in Bitcoin. I know that the hash of a block + nonce must be lower or equal to the given target for mining. Who sets this target ? If ...
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How difficulty variation is technically linked to time take for the block discovery?

Can anybody explain to me technically in units about the time relation to difficulty variation in bitcoin mining e.g. if a block is discovered in 10 minutes, does T = 10 minutes? or T = 20160 minutes ...
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Is there a limit to how many blocks can be rolled back from a 51% attack?

I was wondering if we where to ever face a 51% attack is there some sort of limit as to when the longest chain doesn't matter? For example if I owned 51%+ of the network, mined 1000 blocks privately ...
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Why aren't block hashes used directly as scores for difficulty purposes?

Why does Bitcoin apply a difficulty function to block hashes and then use the output of this function to add up and determine the "longest" chain? Why not just e.g. add together all block hashes (as ...
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Testnet difficulty change

Has something changed recently in testnet? Today I've been seeing new blocks appear every 1-5 seconds instead of the usual 10-20 minutes
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Why is the target truncated?

Reading the docs on target: The maximum target used by SHA256 mining devices is: 0x00000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF Because Bitcoin stores the target as a ...
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Is there any way by which we can see when was last time or which was the block that was created just before bitcoin adjusted its latest difficulty?

I guess if we start doing mathematical calculation then we can easily find exjact block no which was formed just before difficulty was adjusted. But is there anyway around like by using RPC by which ...
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How are difficulty level and block reward determined and stored in decentralized fashion in Bitcoin? [duplicate]

I know the difficulty level and block reward are periodically adjusted in Bitcoin to keep the block time approximately to 10 minutes. I guess these are not determined by a central authority but ...
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Special min difficulty rule for testnet

I heard about this "special difficulty rule" for testnet, which allows blocks with timestamp 20 min later than the last block to have the min difficulty target. So does it mean that the miners can ...
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In Math or Python notation - How to convert bits to difficulty?

Questions What are the equations to convert between bits and difficulty? & understanding bits and difficulty in a block header ask how to convert between bits and difficulty. Unfortunately, I ...
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Calculating the target from the hash leading off bits

I'm implementing my own cryptocurrency and I found it that saving the "hash difficulty” as the leading off (0) bits of a 256 bit number in a SHA-256 hash is the most intuitive. I'm struggling to find ...
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When computing the hash, do you need anything after the number of difficulty bits?

I'm going to screw up a lot of the terminology here. I'm trying to understand the Bitcoin algortihm and wanted to use this JS miner -- https://github.com/howardchung/jsminer . Specifically, I'm ...
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Why is explorers shows different difficulty values?

Just take a random block for example, for block 506068, blockchain.info shows difficulty as 2,603,077,300,218.59, while blockcypher shows 392,962,374, do the explorers use a different way to calculate ...
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Why mining pool has different connections ports for different difficulty

In the documentation of mining pool I found following Connect Details: (Difficulty 5 - GPU) stratum+tcp://stratum.btcprivate.org:3032 (Difficulty 10 - GPU Farm) stratum+tcp://stratum....
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Does a logical mining pool assign harder and harder difficulty to the same miner?

Although every mining pool can do things differently, I wanted to get a handle on how a logical pool would behave. If a miner joins the pool and solves a hash at a low difficult, submits the result ...
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106 views

Why do pools give rewards to miners who solve problems at a lower difficulty than the network?

I'm trying to understand why a pool would want to give rewards to miners who mine at low difficulty. Please tell me where this logic falls apart. If the network difficulty is a nonce ending in 100 ...
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668 views

Probability of Finding a Block

I've been using cryptocurrency revenue calculators and have appeared to figure out that for all of the major algorithms, the probability of a hash being valid is 1/(D*2^u) where u is either 0, 13 (...
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understanding bits and difficulty in a block header

This block: https://blockchain.info/block/00000000000000000025c089d0a7b2bf6241888c4dd90ab7a4c4baa6a2823551 Shows difficulty at 3,007,383,866,429.73, and bits at 392009692. If I want to see how many ...
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How do nonce and difficulty relate?

Good morning, I'm reading about Blockchain technology but I have a couple of questions about the nonce that I cannot find the answers for. I'm hoping someone here will be able to answer them. i) ...
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501 views

Share difficulty and hashrate

Can anybody explain relations and formulas between mining share difficulty, target and hashrate? Thank you.
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Why does bitcoin mining take so long?

I was wondering that a block (Here's a Block #506398) It's nonce is 1,229,291,212 (A little over a billion), Then why does it take so long to mine a block because my system alone can do about 500 GH/...
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56 views

Why can't a Bitcoin fork take over?

According to this question's answers, the difficulty is entirely a result of previous info on a blockchain: How is difficulty calculated? So why can't someone simply fork an earlier state of Bitcoin'...
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How is nbits calculated?

When generating a new block, how is the nbits field in block header calculated? Is nbits calculated for every new block like: nbits=nbits of last block * (timstamp of lastblock-timestamp of (...
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216 views

what is preventing me from changing difficulty every submit when pool mining?

If I do pool mining at difficulty=1000 and I find a share with difficulty=2000, I can tell the pool that I was mining at difficulty=2000 and then submit the share. I can earn more in this way. Does ...
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Is the difficulty in mining a function of how much total mining power there are in the ecosystem?

I'm trying to understand how difficulty works in bitcoin mining. I understand that as there are less and less bitcoins left to be mined, the amount you get for each new block is lowered. The bit I ...
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Will there be a problem if bdiff and pdiff are slightly different?

Considering bitcoin target is 0x00000000FFFF0000000000000000000000000000000000000000000000000000 and pool target is 0x00000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF. Won't pool miner ...
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How to lower difficulty on blockchain?

I created a coin (hexco.in) The problem now is, sometimes some user create pools and use rented mining rigs to mine on my coin. But after a while they stop and my blockchain stucks at a certain block....