Methodology

Block probability

For solo mining calculators, expected blocks over a time window are:

λ = (your hashrate ÷ network hashrate) × (time window ÷ average block time)

The probability of finding at least one block in that window is:

P(≥1 block) = 1 − e^−λ

Expected time and the 63.2% point

Expected time to block is average block time ÷ your network share. It is not a deadline. When λ = 1, meaning elapsed time matches expected time, probability is 1 − e⁻¹ ≈ 63.2%. A 100% target is mathematically unreachable for finite hashrate, which is why the required hashrate calculator stops below 100%.

Expected reward and binary outcome

Expected reward on rental and budget pages is:

expected reward = λ × block reward

That value is a statistical average across many identical attempts. A single solo mining attempt is binary: either the full block reward or nothing. The hashrate rental and budget calculators therefore show both expected value and the most likely binary outcome.

Share timing and difficulty

The share odds calculator models expected share time from hashrate and share difficulty:

expected share time = (difficulty × 2³²) ÷ hashrate

For RandomX (XMR), the code uses difficulty ÷ hashrate instead of difficulty × 2³² ÷ hashrate. The difficulty calculator solves the same relationship in reverse:

difficulty = (hashrate × target interval) ÷ divisor

Required hashrate

The required hashrate calculator inverts the Poisson model:

λ = −ln(1 − P)

It then converts λ back into hashrate with the same network share and time-window relationship used on the main mining calculator.

Budget and opportunity calculations

Budget-based tools first convert USD into BTC using the current BTC/USD price, then convert that budget into affordable rented hashrate from a user-entered BTC-per-unit-per-day rental price. Block probability, expected reward, expected profit, and ROI are then computed with the same formulas above. The mining opportunity calculator sorts results only by block probability. It does not create a blended score.

Cost per 1% block probability

Budget and opportunity pages also show:

cost per 1% probability = budget ÷ (probability × 100)

This is a price-efficiency comparison for similar scenarios. It is not a fixed marginal rate, because probability follows 1 − e^−λ and flattens near 100%.

Limitations

Network hashrate and prices change over time. Rental prices on MiningOdds are editable placeholders, not live quotes. Block time and block reward are fixed protocol constants in the code. The site does not include electricity, hosting, hardware depreciation, taxes, or pool fee modeling beyond what is explicitly shown.

Live data inputs

Network hashrate, coin price, block time, and block reward feed directly into the formulas above. See the data sources page for where that data comes from and how often it refreshes.