[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"mining-farm-info":3,"glossary-related-en-51-attack":7,"glossary-term-en-51-attack":39},{"data":4},{"fpps":5,"btc_rate":6},4.3e-7,94967.34,{"items":8},[9,15,21,27,33],{"id":10,"slug":11,"term":12,"shortDefinition":13,"firstLetter":14},"af6c0c77-882d-462e-9628-8ab4514c9857","sha-256","SHA-256","SHA-256 (Secure Hash Algorithm 256-bit) is a cryptographic hashing function that produces a fixed-length 256-bit hash. It is used in Bitcoin and many other cryptocurrencies for the Proof of Work (PoW) mining process. SHA-256 is used to secure transactions, verify data integrity.","S",{"id":16,"slug":17,"term":18,"shortDefinition":19,"firstLetter":20},"e037bba7-f518-4be0-b772-66ac33c79dad","network-hashrate","Network Hashrate","Network hashrate is the total computational power being used by all miners on the Bitcoin network to solve the cryptographic puzzles required to add new blocks to the blockchain. It is measured in hashes per second (H\u002Fs) and determines how quickly the network can mine new blocks. ","N",{"id":22,"slug":23,"term":24,"shortDefinition":25,"firstLetter":26},"ffe0ce19-e39b-4554-9966-cbaa8c0a928e","asic-downtime","ASIC Downtime","ASIC downtime refers to the period when an ASIC miner is not actively mining cryptocurrency due to hardware issues, maintenance, overheating, power outages, network failures, or other operational problems. During downtime, the miner produces no hashrate and generates no mining rewards.\n","A",{"id":28,"slug":29,"term":30,"shortDefinition":31,"firstLetter":32},"220bab4c-c5a4-4ba7-a527-4e11ed6884cc","cooling-system","Cooling System","A cooling system in Bitcoin mining is a set of equipment and methods used to manage and control the temperature of mining rigs, preventing them from overheating and ensuring that they operate at peak efficiency. Mining rigs, such as ASIC miners, generate a significant amount of heat due to their continuous operation, and if the temperature rises too high, it can lead to performance degradation, hardware failure, or reduced lifespan. ","C",{"id":34,"slug":35,"term":36,"shortDefinition":37,"firstLetter":38},"bdca4f67-3701-4b53-9e2b-2df3166d3b63","bitcoin","Bitcoin","Bitcoin is a decentralized digital currency that allows peer-to-peer transactions without the need for a central authority like a bank or government. It operates on a blockchain, a distributed ledger maintained by a network of computers. Bitcoin is secured through cryptographic algorithms and created through a process called mining, where participants validate transactions and add new blocks to the network.","B",{"term":40},{"id":41,"locale":42,"slug":43,"term":44,"h1":44,"shortDefinition":45,"simpleExplanationHtml":46,"howItWorksHtml":47,"exampleHtml":48,"contentHtml":49,"aliases":50,"abbreviations":51,"algorithms":52,"faq":53,"seoTitle":72,"seoDescription":73,"status":74,"publishedAt":75,"updatedAt":76},"42ca2950-ae1b-4563-90f1-00ce45a500ab","en","51-attack","51% Attack","A 51% attack is a situation where a single miner or mining group controls more than 50% of a blockchain network’s total mining power or hashrate. This gives the attacker enough influence to temporarily control block production and potentially reverse transactions, prevent confirmations, or perform double-spending attacks.","\u003Ch2>\u003Cstrong>51% Attack Explained in Simple Terms\u003C\u002Fstrong>\u003C\u002Fh2>\u003Cp>Blockchain networks are designed to stay secure because mining power is distributed across many participants.\u003C\u002Fp>\u003Cp>If one entity controls most of the network’s hashrate, it can gain too much influence over the blockchain. With more than half of the total mining power, the attacker may be able to create a longer chain faster than the rest of the network.\u003C\u002Fp>\u003Cp>This allows the attacker to:\u003C\u002Fp>\u003Cul>\u003Cli>\u003Cp>reverse recent transactions\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>block transaction confirmations\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>double-spend coins\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Ful>\u003Cp>However, a 51% attack cannot usually:\u003C\u002Fp>\u003Cul>\u003Cli>\u003Cp>create new coins\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>steal coins from other wallets\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>change old blockchain rules\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Ful>\u003Cp>\u003C\u002Fp>","\u003Ch2>\u003Cstrong>How 51% Attack Works\u003C\u002Fstrong>\u003C\u002Fh2>\u003Cp>A 51% attack happens through majority mining control.\u003C\u002Fp>\u003Cp>Here’s how the process works:\u003C\u002Fp>\u003Col>\u003Cli>\u003Cp>\u003Cstrong>Majority Hashrate Obtained\u003Cbr \u002F>\u003C\u002Fstrong> A miner or mining pool gains control of more than half of the network’s total hashrate.\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>\u003Cstrong>Private Chain Mining\u003Cbr \u002F>\u003C\u002Fstrong> The attacker secretly mines an alternative blockchain version.\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>\u003Cstrong>Transaction Broadcast\u003Cbr \u002F>\u003C\u002Fstrong> The attacker sends cryptocurrency to a victim, such as an exchange or merchant.\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>\u003Cstrong>Secret Chain Grows Longer\u003Cbr \u002F>\u003C\u002Fstrong> The attacker continues mining the hidden chain without including the public transaction.\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>\u003Cstrong>Longer Chain Released\u003Cbr \u002F>\u003C\u002Fstrong> If the secret chain becomes longer, the network accepts it as valid.\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Fol>\u003Cp>Bitcoin follows this rule:\u003C\u002Fp>\u003Cp>Valid Chain=Chain With Most Accumulated \u003C\u002Fp>\u003Col>\u003Cli>\u003Cp>\u003Cstrong>Transaction Reversed\u003Cbr \u002F>\u003C\u002Fstrong> The original payment disappears from the blockchain, allowing double spending.\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Fol>\u003Cp>\u003C\u002Fp>","\u003Ch2>\u003Cstrong>Example of a 51% Attack\u003C\u002Fstrong>\u003C\u002Fh2>\u003Cp>Imagine a small cryptocurrency network with low mining activity.\u003C\u002Fp>\u003Cp>A mining company gains 60% of the total hashrate.\u003C\u002Fp>\u003Cp>The attacker:\u003C\u002Fp>\u003Cul>\u003Cli>\u003Cp>sends coins to an exchange\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>trades them for another asset\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>secretly mines a private chain excluding the transaction\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Ful>\u003Cp>After withdrawing funds:\u003C\u002Fp>\u003Cul>\u003Cli>\u003Cp>the attacker publishes the longer chain\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>the network reorganizes\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>the exchange transaction disappears\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Ful>\u003Cp>The attacker keeps both:\u003C\u002Fp>\u003Cul>\u003Cli>\u003Cp>the original coins\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>the withdrawn assets\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Ful>\u003Cp>\u003C\u002Fp>","\u003Ch2>\u003Cstrong>Why Bitcoin Is Resistant to 51% Attacks\u003C\u002Fstrong>\u003C\u002Fh2>\u003Cp>Large networks like Bitcoin are extremely difficult to attack because they require enormous mining power and electricity costs.\u003C\u002Fp>\u003Cp>Bitcoin protection comes from:\u003C\u002Fp>\u003Cul>\u003Cli>\u003Cp>massive global hashrate\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>decentralized mining\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>high ASIC hardware costs\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>energy requirements\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Ful>\u003Cp>The cost of attacking Bitcoin is usually far higher than the potential reward.\u003C\u002Fp>\u003Ch2>\u003Cstrong>Smaller Networks Are More Vulnerable\u003C\u002Fstrong>\u003C\u002Fh2>\u003Cp>Cryptocurrencies with:\u003C\u002Fp>\u003Cul>\u003Cli>\u003Cp>low hashrate\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>fewer miners\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>limited decentralization\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Ful>\u003Cp>are much easier to attack.\u003C\u002Fp>\u003Cp>Several smaller Proof of Work coins have experienced real 51% attacks in the past.\u003C\u002Fp>\u003Ch2>\u003Cstrong>51% Attack and Double Spending\u003C\u002Fstrong>\u003C\u002Fh2>\u003Cp>The main danger of a 51% attack is double spending.\u003C\u002Fp>\u003Cp>Double spending means:\u003C\u002Fp>\u003Cul>\u003Cli>\u003Cp>spending the same coins twice by reversing transactions after receiving goods or services.\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Ful>\u003Ch2>\u003Cstrong>How Networks Reduce 51% Attack Risk\u003C\u002Fstrong>\u003C\u002Fh2>\u003Cp>Blockchain networks reduce attack risk through:\u003C\u002Fp>\u003Cul>\u003Cli>\u003Cp>decentralization\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>large miner participation\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>confirmation requirements\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>high mining costs\u003C\u002Fp>\u003C\u002Fli>\u003Cli>\u003Cp>distributed mining pools\u003C\u002Fp>\u003C\u002Fli>\u003C\u002Ful>\u003Cp>Exchanges also reduce risk by waiting for multiple confirmations before accepting deposits.\u003C\u002Fp>",[],[],[],[54,57,60,63,66,69],{"answer":55,"question":56},"A 51% attack happens when one miner or mining group controls more than half of a blockchain network’s total mining power.","What is a 51% attack?",{"answer":58,"question":59},"Attackers may reverse recent transactions, block confirmations, and perform double-spending attacks.","What can happen during a 51% attack?",{"answer":61,"question":62},"No. A 51% attack usually cannot directly steal coins from other users’ wallets or create new coins.","Can a 51% attack steal coins from wallets?",{"answer":64,"question":65},"Technically yes, but the cost and infrastructure required to attack Bitcoin are extremely large, making it highly impractical.","Is Bitcoin vulnerable to a 51% attack?",{"answer":67,"question":68},"Smaller networks often have lower hashrates and fewer miners, making majority control easier to obtain.","Why are smaller cryptocurrencies more vulnerable?",{"answer":70,"question":71},"Exchanges usually wait for multiple blockchain confirmations before accepting cryptocurrency deposits as final.","How do exchanges protect against 51% attacks?","51% Attack in Blockchain: Definition and How It Threatens ","What is a 51% attack in blockchain? Learn how majority hashpower attacks work, how they affect Bitcoin and other cryptocurrencies, and why decentralization is important for network security","published","2026-06-03T17:43:33.268Z","2026-06-03T17:43:28.818Z"]