On February 14, 2022, Monero faced one of its most discussed network security moments: it emerged that the mining pool MineXMR was responsible for approximately 44% of Monero's total hash rate. Hash rate is the measure of total computational power contributing to a proof-of-work blockchain — effectively, how much combined computing effort is securing the network. When any single entity approaches control of more than half that power, the risk of a 51% attack becomes a live concern rather than a theoretical one.
Understanding the 51% Attack Risk
A 51% attack is considered one of the most serious threats to a proof-of-work blockchain. When a group gains majority hash power, it can reorganize recent blocks — rewriting the record of which transactions were confirmed. The primary practical exploit this enables is double-spending: spending the same coins twice by broadcasting one transaction publicly while secretly mining an alternative chain that replaces it.
This is not a hypothetical concern limited to small networks. Bitcoin SV, Bitcoin Gold, and Ethereum Classic have all experienced 51% attacks — with Ethereum Classic hit three separate times before its community implemented additional protections. No network operating on proof-of-work is structurally immune if hash rate becomes sufficiently concentrated.
However, a 51% attacker's capabilities are specifically bounded. Monero moderator u/dEBRUYNE_1 clarified the limits on Reddit at the time: double-spends are detectable, and even a dominant mining pool cannot reverse already-confirmed transactions beyond a short window, create new XMR from nothing, spend coins from wallets they do not control, or alter Monero's emission schedule or block reward parameters. The risk is real but narrower than the term "51% attack" sometimes implies.
Community Response
When MineXMR's hash rate dominance became widely known, the Monero community responded through the most direct lever available: coordinated social pressure on individual miners. The message across Reddit, Monero forums, and social channels was consistent — leave MineXMR and redistribute hash rate to smaller pools.
The effects were measurable. Daily transaction counts dropped from approximately 40,000 to around 19,000 in the weeks that followed — a consequence of reduced network activity during the uncertainty — and XMR's price fell to 64% below its all-time high. MineXMR's administrator u/xnbya acknowledged user concerns on Reddit and announced a fee increase from 1% to 1.1%, effective April 1, 2022. Many in the community found this response insufficient given the scale of the centralization concern.
One factor raised in community discussions: MineXMR had a known physical location in the United Kingdom, where executing a 51% attack would potentially carry significant legal consequences — an additional deterrent beyond technical feasibility.
Resolution: MineXMR Shutdown and the P2Pool Era
The situation resolved itself more decisively than many expected. On August 12, 2022, MineXMR permanently shut down operations, with its announcement explicitly recommending all miners transition to P2Pool — Monero's decentralized peer-to-peer mining pool. P2Pool has no central operator, charges no pool fees, and cannot accumulate dominant hash rate by design. The Monero community broadly welcomed the announcement; XMR rose approximately 8% within an hour of its publication.
The MineXMR episode established a clear community norm: no single pool should hold more than roughly a third of Monero's hash rate, and P2Pool is the recommended default for miners who want to contribute to network health rather than centralization risk. As of 2026, P2Pool accounts for a meaningful share of Monero's mining activity, and the community continues to actively discourage concentration in any single pool.
Protecting Your Mining Rewards
Whether you mine Monero solo, via P2Pool, or through another pool, your payout destination is a wallet address you control. XMRWallet is a free, open-source, browser-based Monero wallet that requires no software installation or registration. Set it as your mining payout address and your rewards go directly into a wallet where you — and only you — hold the keys.
Frequently Asked Questions
Should I use P2Pool or a traditional mining pool for Monero in 2026?
P2Pool is the Monero community's preferred option because it eliminates pool-level centralization risk entirely. It requires running a local Monero node (which also supports the network) and has no pool fees. Traditional pools are simpler to set up and may have more consistent payout timing for miners with lower hash rates, but come with the centralization trade-off the MineXMR situation illustrated. If running a full node is feasible, P2Pool is strongly preferred.
How do I find out the current hash rate distribution across Monero pools?
Sites like miningpoolstats.stream/monero provide real-time data on hash rate distribution across active Monero mining pools. The Monero community recommends checking this periodically and switching pools if any single pool approaches 30-40% of total hash rate.
