API reference

GET /api/index

Live kimchi premium from Upbit, Bithumb and the ECB. Read-only, no key, cached 8 seconds on the server.

Response fields

Field	Type	Meaning
`at`	number	server time of the reading, ms since epoch
`spot`	number or null	live index in pp: median of the two tickers ÷ latest ECB fix − 1
`upbit.price`	number	last Upbit KRW-USDT trade, won
`upbit.vol24hKrw`	number	Upbit 24-hour traded value, won
`bithumb.price`	number	last Bithumb USDT/KRW close, won
`bithumb.vol24hKrw`	number	Bithumb 24-hour traded value, won
`ecb.rate`	number	ECB USD/KRW reference rate
`ecb.date`	string	date of that fix, YYYY-MM-DD
`rolling`	object or null	trailing 24-hour average index from hourly closes
`last`	object or null	the value the last expiry would settle at
`window`	object	the next expiry, when its 24-hour window opens, samples in so far
`expiries.upcoming`	number[]	the next expiries, ms since epoch
`errors`	object	per-source error text, null when that source answered

Example

{
  "spot": 0.39,
  "upbit": { "price": 1364, "vol24hKrw": 54200000000 },
  "bithumb": { "price": 1364, "vol24hKrw": 55993094549 },
  "ecb": { "rate": 1358.73, "date": "2026-11-06" }
}

When a source fails, its field is null, spot is null, and errors names the source. The endpoint never invents a value.

Units

Unit	Meaning
pp	percentage point of premium
ibp	index basis point, 1 pp = 100 ibp; the program stores prices and S in ibp
unit	one micro-USDC per ibp of distance; a $10-per-point contract is 100,000 units