BTC: Local Mempool 99th Percentile Entry Age

Bitcoin Local Mempool 99th Percentile Entry Age was 919,740 seconds on 9 Nov 2026 (latest daily value).

The 99th-percentile local entry age across captured mempool transactions, in seconds.

Why use it. Inspect the extreme local residence-time tail without claiming network-wide latency. How to read it. This is a nearest-rank observed age, not an interpolated percentile or confirmation forecast. Empty populations are undefined. The hour/day point is the last actual accepted sample in that UTC bucket, not a time average. Earlier or missing samples and departed/replaced transactions are not reconstructed. Read capture clocks and gap coverage; a final sampling-period label does not confirm its transactions.

Calculation. Use one validated Core capture with consistent local clocks and dependencies. Order exact capture-minus-entry ages by transaction count; select one-based rank ceil(0.99 × count). Age is local capture Unix second minus Core-reported local entry second, not network first-seen time or expected confirmation wait. Transactions have equal weight; virtual size does not weight age. Only one local Bitcoin Core node is observed; this is not a worldwide mempool census or a confirmation forecast.