Median block delay
The median delay until a pool sends its first valid block template, compared with the earliest valid template seen for the same Bitcoin block and region. Lower is better. The dashboard uses the latest 24 hours.
Method 2026-08-04.22
How the measurements work.
StratumStats measures several independent parts of pool performance. It does not combine them into an overall score or declare one pool universally best.
Dashboard metrics
P95 block delay
The 95th-percentile delay. Ninety-five percent of measured deliveries were this fast or faster, so P95 exposes occasional stalls that the median may hide.
Availability
Valid block-template deliveries divided by observations where the probe was connected and eligible to receive one. The dashboard shows both the percentage and sample count.
Estimated mining loss
Median relative delay divided by Bitcoin’s 600-second target block interval. This estimates incremental stale-work time; it is not measured payout or revenue loss.
TCP connection
Time to establish the basic network connection to a pool, including local name lookup.
TLS handshake
Time to establish an encrypted connection and verify the pool’s certificate, hostname, validity period, and trusted issuer.
mining.subscribe
The Stratum request that starts a mining session.
mining.authorize
The Stratum request that asks the pool to accept the worker identity.
How pools are compared
Block-template delay is compared only for the same Bitcoin block observed from the same region. This reduces differences caused by geography and clock timing. Median, P95, history, and Stratum response timings use a rolling 24-hour window; availability and payout verification remain cumulative.
A valid coinbase-only template counts as delivery because it lets miners stop working on the previous block immediately. Empty-first frequency is retained as raw evidence but is not displayed or scored.
Coinbase payouts and fees
The probe reconstructs each valid coinbase transaction and checks whether an output matches its generated worker address. That address is discarded before data is published.
For a solo pool with a matched worker output, the observed effective fee is 100 × (total coinbase value − worker payout) ÷ total coinbase value. Donations or configured payout splits may be included in that percentage.
Shared-pool miner fees cannot be measured from the block coinbase because participant balances and later payouts are handled separately. Shared-pool rows therefore show operator-published terms and the date they were checked.
A non-worker destination is a positive-value coinbase output that did not match the probe worker script. It may be a pool fee, donation, witness commitment, payout split, or another participant; it does not prove ownership.
Pool groups
Free solo pools have a consistently matched worker payout and a latest observed fee of 0.00%. Paid solo pools have a matched payout and either a nonzero or not-yet-measured fee. Unverified solo pools remain separate until the worker payout is consistently confirmed.
PPLNS means Pay Per Last N Shares: rewards are based on work submitted during a recent share window. Other shared pools use different payout methods.
What is excluded
Pool size, popularity, sponsorship, paid placement, subjective reputation, and any composite score. Published fee terms are shown as pool claims, not probe measurements.
Privacy and disclosures
Operational details that could identify measurement traffic are intentionally withheld. Published results are aggregated to protect measurement integrity.
- Reports use automated observations only; no pool pays or applies for placement.
- Latency is relative within the same block and vantage, reducing geographic bias.
- Block-template latency, latency history, and protocol timing statistics use a rolling 24-hour window.
- Eligible block and protocol-attempt counts are published directly with their measurements.
- The probe uses pseudonymous miner credentials, but a pool can still observe its source IP.
- Observed solo-pool fee is inferred only when a decoded coinbase output matches the generated worker script; optional donations or splits may be included.
- Matched worker payout destinations are reduced to aggregate verification and fee evidence; their address and script are never published.
- Coinbase destinations identify decoded output scripts, not who controls a non-worker address.