Documentation

ticker - the ticker (symbol) of the ETF
dt - the as of date as specified on the issuer's website (ISO 8601 format)
holdings - the issuer's BTC holdings
change - the change in holdings compared to the prior day
notes - notes on any calculation performed to arrive at holdings
update_ts - update timestamp in UTC (ISO 8601 format)
error - whether there was an error loading current data. If true, data is returned from the last successful day.

Data for Supported ETFs

Ticker	Description	Holdings	Change	Change %	As of Date	BT
ARKB	ARK 21Shares Bitcoin ETF	37,022	-83	-0.22	2026-05-01	BT
BITB	Bitwise Bitcoin ETF	38,397	+347	+0.91	2026-04-30	BT
BTC	Grayscale Bitcoin Mini Trust ETF	53,002	0	0.00	2026-05-01	BT
BTCC	Purpose Bitcoin ETF	19,091	-35	-0.18	2026-05-01	BT
FBTC	Fidelity Wise Origin Bitcoin Fund	185,797	+348	+0.19	2026-04-30	BT
GBTC	Grayscale Bitcoin Trust ETF	150,743	-83	-0.06	2026-05-01	BT
IBIT	iShares Bitcoin Trust ETF	810,326	+249	+0.03	2026-04-30	BT