How do I calculate my block finding probability from my hashrate?

Your chance of finding a Monero block depends on your hashrate, the network’s mining difficulty, and how long you mine. The key formula is probability of at least one block = 1 − e^(−expected blocks)—so an average waiting time is not a deadline or a guarantee.

Gather the right numbers

You need three inputs:

• Your hashrate (H): how many mining calculations your device completes each second, measured in hashes per second (H/s).
• Mining time (t): the time you will actually spend mining, in seconds.
• Network difficulty (D): a number that represents the average work needed to find a valid block. Get it from a current Monero explorer or your node.

Convert your hashrate before calculating: 1 kH/s = 1,000 H/s and 1 MH/s = 1,000,000 H/s.

Use your sustained, measured Monero RandomX hashrate, not a brief peak or a benchmark for another mining algorithm. If you mine in a browser, allow for paused tabs, overheating, and other interruptions.

Calculate your chance

First, calculate the expected number of blocks:

λ = H × t ÷ D

Here, λ (“lambda”) means the average number of blocks you would find across many comparable mining periods.

Then calculate your chance of finding at least one:

P = 1 − e^(−λ)

The number e is a standard mathematical constant, about 2.71828. You can enter this in a spreadsheet as:

=1-EXP(-(H*t/D))

Multiply the result by 100 to get a percentage.

You can also estimate expected blocks from your share of the network:

λ ≈ (your hashrate ÷ network hashrate) × (seconds mining ÷ 120)

This uses Monero’s roughly two-minute block time. Use a live network estimate, not an old figure.

Work through a hypothetical example

Suppose you mine at 10,000 H/s, and the network runs at 1,000,000,000 H/s. These are example numbers, not current measurements.

Your share is:

10,000 ÷ 1,000,000,000 = 0.00001

Monero produces roughly 720 blocks per day, so your expected daily blocks are:

λ ≈ 0.00001 × 720 = 0.0072

That gives you:

• One day: about a 0.72% chance of at least one block.
• 30 days: about a 19.4% chance.
• About 139 days: roughly a 63.2% chance, not 100%.

Those results assume continuous mining and unchanged network conditions.

Interpret the result correctly

Your average waiting time is D ÷ H seconds. At that time, your chance of finding at least one block is only about 63.2%. Mining has no “overdue” bonus: previous unsuccessful attempts do not improve your next attempt.

Monero’s difficulty adjusts every block. For changing conditions, calculate expected blocks for each period, add them together, then apply 1 − e^(−total).

For P2Pool, a decentralized mining pool, this formula describes your chance of personally finding a full Monero block—not your payout frequency. P2Pool also tracks easier proofs of work called shares, which determine eligibility for shared rewards.

Running a node does not multiply your odds. Staying connected and mining current work helps avoid wasted effort.

The bottom line

Calculate expected blocks first, then convert that number into a probability. Treat the result as a chance under stated assumptions—not a promised block date or payout schedule.