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	39,023	0	0.00	2025-12-15	BT
BITB	Bitwise Bitcoin ETF	40,413	0	0.00	2025-12-11	BT
BTC	Grayscale Bitcoin Mini Trust ETF	48,868	-119	-0.24	2025-12-12	BT
BTCC	Purpose Bitcoin ETF	20,018	+3	+0.01	2025-12-12	BT
FBTC	Fidelity Wise Origin Bitcoin Fund	202,403	-21	-0.01	2025-12-12	BT
GBTC	Grayscale Bitcoin Trust ETF	166,870	-139	-0.08	2025-12-12	BT
IBIT	iShares Bitcoin Trust ETF	778,052	+567	+0.07	2025-12-12	BT