On-chain cost index

What a $10,000 round trip in tokenized US stocks costs on public blockchains: buy, then sell the same tokens straight back, fees and price impact included. One number a day, worked out from every pool we record on Solana, Robinhood Chain, Base and BNB Chain.

Tue 27 Oct 2026, UTC · 96 readings · updated every morning · free to quote with credit

1 bp is 0.01%: 12.5 bp is $12.50 on $10,000.

Day by day

The last 14 finished days, in bp. Published each morning from 28 October 2026; the days before 27 October were worked out afterwards from readings we recorded at the time, by the same rule. Every day from Mon 12 Oct 2026: cost-index.csv.

Note 1. Not shown: on 18 to 26 October we did not read the new pools that opened on Base (see Corrections), so the index for these days would be too high. If we can work these days out from the chain's own records, they will appear here, marked as such.

Note 2. Worked out afterwards, on 27 October 2026, from readings we recorded at the time, by the same rule. The index has been published each morning since 28 October 2026.

The ten on Tue 27 Oct

Each stock’s cheapest round trip, the median of the day’s readings, in bp, and the chain where it was cheapest most often.

How the index is made

• The stocks are fixed: ten big US stocks and funds, SPY, QQQ, NVDA, TSLA, AAPL, GOOGL, META, CRCL, MSTR and COIN, written down before the first number.
• Every 15 minutes: for each of the ten, the cheapest $10,000 round trip among every pool we record for that stock on the four chains we read (Solana, Robinhood Chain, Base and BNB Chain), any issuer: its best venue. The reading’s index is the median of the ten, each counting equally. Not weighted by company size, because a company’s stock market value says nothing about how easily its tokens trade; the median, not the mean, so one or two stocks cannot move it. With an even number of stocks, the median is the average of the middle two. A reading with fewer than 7 of the ten has none.
• The day: the median of its readings, all hours and by session in New York time: US market hours (9:30 to 16:00 on the days the US market is open, to 13:00 on its early-close days), US market closed (the other weekday hours, holidays included) and the weekend.
• Which pools count: a pool counts on a day only if its own price took 3 or more values, 0.1% or more apart, that day or the day before, so a pool nobody trades cannot pull the number down.
• Nothing traded: each round trip is worked out from the pool’s own state on the chain, the way the pool would fill it: buy with its dollar coin, then sell the same tokens straight back, fees and price impact included.
• Never overwritten: a published number is never replaced by another. If we find an error in a finished day that moved its all-hours number by 1 bp or more, we withdraw it: the day shows a dash and a dated note that keeps the number as first published. A smaller error gets a dated note beside the number. A dash, a day we could not measure correctly or a withdrawn one, gets a number only if that day can be worked out again from the chain’s own records, and is then marked as worked out afterwards, with the date. Every case is listed below, newest first.
• Changes: a change to these rules is announced here at least 30 days before it applies, gets a new version and a date, and applies from that date only; adding a chain is such a change. The ten are reviewed once a year. If fewer than 7 of the ten can be measured for 30 days in a row, the index stops and says so.
• Cases: 1. 27 October 2026, before the first publication: 18 to 26 October are shown as dashes from the start. On those days we did not read the new pools that opened on Base (see Corrections), so their numbers would have been too high; they were never published as numbers.