Mempool Size by Fee Rate Tier
- 1M1M
- 3M3M
- 6M6M
- 1Y1Y
- ALLALL
- ValueValue
- ShareShare
About this metric
What it measures
Mempool Size by Fee Rate Tier sums the virtual sizes of unconfirmed transactions within each of nine fee-rate bands. Values are virtual bytes (vB), while labels such as 1–2 sat/vB, 10–50 sat/vB and 50+ sat/vB identify the offered fee rate.
How to read it
More virtual bytes in a band mean more block space is needed to clear that part of the queue. Growing higher-rate bands indicate competition ahead of lower-rate bids. The 10–50 sat/vB series reached about 137.47 million vB on January 27, 2024, much larger than its full-history median near 84,500 vB.
Virtual size accounts for transaction weight and is not raw serialized bytes or a node’s RAM usage. Transactions may depend on parents, miners choose packages, and new arrivals change the queue. This daily size profile provides context for congestion, not an exact number of blocks until confirmation.
- Frequency
- Daily (UTC 00:00)
- Asset
- BTC
- Category
- Mempool
- Type
- Breakdown
- Unit
- vB
- Data since
- 2021-10-15
- Latest data
- 2026-10-27
FAQ
How do virtual bytes differ from ordinary bytes?
Virtual size is transaction weight divided by four, rounded up to a whole vbyte. Witness data contributes less weight than other transaction data, so virtual size can be smaller than serialized size.
Why compare size by fee tier rather than transaction count?
Transactions can differ greatly in size. Summing virtual bytes shows the block-space demand within each price band, while counting transactions treats a small transfer and a large consolidation equally.
Can I add the bands to estimate the pending size?
They partition the observed queue by fee rate, so adding them gives its represented virtual size, subject to rounding. Separate daily series may not reconcile exactly if their observation or aggregation methods differ.
