Does solo mining reduce the risk of 51 percent attacks?

Yes—solo mining can reduce the risk of a 51 percent attack on Monero if it spreads mining power across more independent people. But solo mining is not an automatic shield: what matters is who controls the mining power, not simply how many miners or nodes exist.

Why control matters more than the mining label

A 51 percent attack happens when someone controls enough mining power to reliably outpace the rest of the network. Mining power, also called hashrate, is the rate at which equipment performs the calculations used to compete for blocks.

An attacker with a sustained majority could:

• Reverse some of their own recent payments and try to spend those coins again.
• Keep selected transactions out of the blocks they produce.
• Replace recent blocks made by honest miners.

They could not simply take coins from your wallet or create coins outside Monero’s rules.

The key question is therefore: How much mining power can one party direct? A thousand computers taking instructions from one operator can still represent one point of control.

How solo mining can help

When you solo mine through your own Monero node, your setup chooses the transactions for your candidate blocks. A node is software that checks and shares blocks and transactions according to Monero’s rules.

This removes a pool operator from the decision-making path. With a traditional mining pool, many miners combine their work for more regular payouts, while the operator generally decides what block they work on.

If you move existing hashrate from a very large pool to independent solo mining:

• The network’s total hashrate stays roughly the same.
• That pool controls a smaller share.
• Mining decisions become less concentrated.

That can make an attack through a dominant pool harder. Pool participants can leave a suspicious operator, but noticing a problem and switching takes time.

What solo mining does not solve

Solo mining does not make your hardware contribute more security per calculation. If an attacker already controls most of the hashrate, relabeling the remaining miners as “solo” does not remove that advantage.

The starting point also matters. Moving from a small, independent pool to solo mining may change concentration only slightly. Adding new honest hashrate can make an attack harder whether you contribute through solo mining or a well-designed decentralized pool.

Likewise, one company operating many solo-mining machines is still one decision-maker.

Running a node without mining helps you verify Monero independently, but it adds no hashrate. More nodes alone cannot defeat a majority-hashrate attack.

Where P2Pool fits into your choice

P2Pool is a decentralized mining pool: it lets you share rewards without handing block-building control to a central pool operator.

With a properly configured P2Pool setup using your own node, you retain independent block construction while getting more frequent payout opportunities than solo mining. Payouts still depend on your contribution and pool luck.

This matters because solo mining with a small CPU can mean an extremely long wait for a reward. You do not have to accept that uncertainty just to avoid concentrating power in a traditional pool.

The bottom line

Solo mining helps when it creates genuinely independent control or takes hashrate away from a dominant operator. It is decentralization—not the “solo” label—that reduces the risk. P2Pool offers another way to support that goal without relying on a central pool operator.