[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"glossary-term-en-uncle-block":3,"glossary-related-en-uncle-block":38},{"term":4},{"id":5,"locale":6,"slug":7,"term":8,"h1":8,"shortDefinition":9,"simpleExplanationHtml":10,"howItWorksHtml":11,"exampleHtml":12,"contentHtml":13,"aliases":14,"abbreviations":15,"algorithms":16,"faq":17,"seoTitle":33,"seoDescription":34,"status":35,"publishedAt":36,"updatedAt":37},"7108b9fd-0511-41e0-90b7-a63d37e949ad","en","uncle-block","Uncle Block","An uncle block is a valid block in Ethereum that is mined but not included in the main blockchain because another block at the same height has already been added. Unlike orphan blocks in Bitcoin, uncle blocks are accepted by the Ethereum network and reward miners with a smaller incentive.","\u003Cp>An uncle block in Ethereum is a block that a miner successfully mines but is not included in the main chain due to another miner’s block being accepted first at the same height. Unlike orphan blocks in Bitcoin, uncle blocks are not discarded entirely; instead, they are rewarded with a smaller fee.\u003C\u002Fp>\u003Cp>In the Ethereum network, multiple blocks can be mined at the same block height, but only one block can be added to the main chain. The other blocks that are mined during this time are considered \"uncles.\" While uncle blocks are not included in the main chain, they are still recognized by the network, and miners who find uncle blocks receive partial rewards for their efforts.\u003C\u002Fp>\u003Cp>Uncle blocks are a way for the Ethereum network to maintain mining incentives and promote decentralization, ensuring that miners continue to participate and are not penalized too harshly when their blocks are not accepted.\u003C\u002Fp>","\u003Cp>In Ethereum, when two miners find a block at the same height, the network will accept the first block it receives and broadcast it to other nodes. The second block, while valid, is not added to the main chain and becomes an uncle block.\u003C\u002Fp>\u003Cp>The Ethereum network includes uncle blocks in the blockchain to reward miners who find valid blocks that aren’t added to the main chain. Instead of being discarded, uncle blocks are referenced in the blockchain as \"uncle references.\"\u003C\u002Fp>\u003Cp>Miners who successfully find uncle blocks are rewarded with a portion of the block reward, though the reward is smaller than the full block reward for a block added to the main chain. The size of the reward depends on the uncle's proximity to the main chain and the number of uncles included.\u003C\u002Fp>\u003Cp>The concept of uncle blocks is unique to Ethereum and serves to increase the security and decentralization of the network. By rewarding miners for finding uncles, Ethereum encourages more mining activity, even if a miner’s block is not included in the main chain.\u003C\u002Fp>","\u003Cp>Imagine a scenario where two miners, Miner A and Miner B, both solve a block at the same time. Miner A’s block is broadcast and added to the main Ethereum blockchain, while Miner B’s block, although valid, is not added to the chain and becomes an uncle.\u003C\u002Fp>\u003Cp>The Ethereum network recognizes Miner B’s block as a valid uncle block and rewards Miner B with a smaller portion of the block reward. If Miner B’s block was added as an uncle to a subsequent block, Miner B would receive part of the reward from the block that references their uncle.\u003C\u002Fp>\u003Cp>For example, if Miner A finds a block at height 1000, and Miner B finds an uncle at the same height, the main chain includes Miner A’s block, and Miner B’s block becomes an uncle. Miner B would receive a portion of the block reward based on the distance between the uncle block and the block that referenced it.\u003C\u002Fp>","\u003Cp>This system encourages decentralization and ensures that miners who mine valid blocks are still rewarded, even if their block isn’t included in the main chain.\u003C\u002Fp>",[],[],[],[18,21,24,27,30],{"answer":19,"question":20},"Uncle blocks in Ethereum are valid blocks that are not included in the main chain but are still rewarded with a smaller incentive. In Bitcoin, orphan blocks are discarded entirely and are not rewarded. Ethereum’s system allows for the inclusion of uncles to encourage decentralization, while Bitcoin discards orphan blocks without rewards.","How do uncle blocks differ from orphan blocks in Bitcoin?",{"answer":22,"question":23},"Uncle blocks help maintain network security and decentralization by rewarding miners who mine blocks that are not included in the main chain. This encourages miners to continue contributing to the network even if their blocks are not part of the main chain.","Why are uncle blocks important in Ethereum?",{"answer":25,"question":26},"Miners receive a smaller reward for finding uncle blocks, based on the distance between the uncle block and the block that references it. The closer the uncle block is to the main chain, the larger the reward it receives.","How are rewards for uncle blocks distributed?",{"answer":28,"question":29},"No, uncle blocks do not affect the average block time in Ethereum. They are simply blocks that were not included in the main chain but are still rewarded. The block time in Ethereum is still targeted at around 12-15 seconds per block.","Do uncle blocks affect Ethereum’s block time?",{"answer":31,"question":32},"Yes, a miner can submit more than one uncle block, but only the first block to be broadcast and accepted by the network is added to the main chain. Any subsequent blocks found at the same height will be treated as uncle blocks and rewarded accordingly.","Can a miner submit more than one uncle block?","Uncle Block: Definition, Role, and Comparison with Orphan Blocks","What is an uncle block in Ethereum? Learn how uncle blocks work in Ethereum mining, why they are accepted by the network, and how they differ from orphan blocks.\n","published","2026-04-30T11:17:34.041Z","2026-04-30T11:17:29.647Z",{"items":39},[40,46,52,58,63],{"id":41,"slug":42,"term":43,"shortDefinition":44,"firstLetter":45},"1364c051-589f-47a8-95be-e219b6df8afc","orphan-block","Orphan Block","An orphan block is a block that is valid but is not accepted into the main blockchain because another block at the same height has already been accepted. Orphan blocks occur when two miners find a block at roughly the same time, but only one can be added to the blockchain. ","O",{"id":47,"slug":48,"term":49,"shortDefinition":50,"firstLetter":51},"242b3942-7bae-4185-8612-f585a60ae856","maintenance-fee","Maintenance Fee","The maintenance fee in Bitcoin mining refers to the cost associated with maintaining mining hardware and ensuring its continuous operation. This fee is typically charged by cloud mining providers or mining pools to cover the costs of electricity, hardware upkeep, cooling systems, and other operational expenses. The maintenance fee is usually a percentage of the mined cryptocurrency, which is deducted before payouts are made to miners.","M",{"id":53,"slug":54,"term":55,"shortDefinition":56,"firstLetter":57},"b629f53f-5dba-4dc0-b655-16f1f17682bd","firmware","Firmware","Firmware is a type of software that is embedded into hardware devices like Bitcoin miners to control their operations. In the context of mining hardware (such as ASIC miners), firmware manages the device’s basic functions, including the mining algorithm, power management. ","F",{"id":59,"slug":60,"term":61,"shortDefinition":62,"firstLetter":51},"5aee08d1-8bed-4d12-b8ac-7a81595e495c","mining-contract","Mining Contract","A mining contract is an agreement between a miner and a cloud mining provider or mining service that allows the miner to rent computational power for a specified period. In exchange for the rental, the miner receives a portion of the cryptocurrency mined based on the rented mining power. Mining contracts can vary in terms of duration, cost, and the type of mining power rented (hashrate).",{"id":64,"slug":65,"term":66,"shortDefinition":67,"firstLetter":51},"6281494e-2b6d-4956-9f7e-46a76a12920e","mining-target","Mining Target","A mining target is a numeric value that defines the difficulty of finding a valid hash in Bitcoin mining. Miners must find a hash that is lower than or equal to the target value in order to successfully mine a new block. "]