Klines Stream

Streaming candlestick (OHLCV) updates for a symbol and interval.

WebSocket URL: wss://stream.pipai.io/ws

Subscription

Subscribe:

{
  "op": "subscribe",
  "channel": "market.klines",
  "params": { "symbol": "BTCUSDT", "interval": "1m" },
  "req_id": "client-201"
}

Unsubscribe:

{
  "op": "unsubscribe",
  "channel": "market.klines",
  "params": { "symbol": "BTCUSDT", "interval": "1m" },
  "req_id": "client-202"
}

Subscription parameters

Name	Type	Mandatory	Description
symbol	string	Yes	Trading pair, uppercase, e.g. BTCUSDT.
interval	enum	Yes	One of 1m, 3m, 5m, 15m, 30m, 1h, 2h, 4h, 6h, 8h, 12h, 1d, 3d, 1w, 1M.

Payload

In-progress bar update:

{
  "event": "kline",
  "ts": 1745923200250,
  "symbol": "BTCUSDT",
  "interval": "1m",
  "kline": {
    "open_time": 1745923200000,
    "close_time": 1745923259999,
    "open": "67432.15",
    "high": "67450.50",
    "low": "67430.00",
    "close": "67442.80",
    "volume": "12.3421",
    "quote_volume": "832104.55",
    "trades": 142,
    "taker_buy_volume": "6.8810",
    "taker_buy_quote_volume": "464012.31",
    "is_closed": false
  }
}

Final close push for the bar:

{
  "event": "kline",
  "ts": 1745923260001,
  "symbol": "BTCUSDT",
  "interval": "1m",
  "kline": {
    "open_time": 1745923200000,
    "close_time": 1745923259999,
    "open": "67432.15",
    "high": "67498.80",
    "low": "67410.00",
    "close": "67498.80",
    "volume": "201.7710",
    "quote_volume": "13612498.55",
    "trades": 2014,
    "taker_buy_volume": "112.4421",
    "taker_buy_quote_volume": "7588321.42",
    "is_closed": true
  }
}

Payload fields

Field	Type	Description
event	string	Always "kline".
ts	integer	Server push time, Unix milliseconds.
symbol	string	Trading pair, uppercase.
interval	string	Bar interval, echoed from the subscription.
kline	object	Candlestick payload (see below).

kline object

Field	Type	Description
open_time	integer	Bar open time, Unix milliseconds.
close_time	integer	Bar close time, Unix milliseconds (last ms of the bar).
open	string (decimal)	Open price.
high	string (decimal)	High price so far in the bar.
low	string (decimal)	Low price so far in the bar.
close	string (decimal)	Most recent traded price.
volume	string (decimal)	Cumulative volume in base asset for the bar.
quote_volume	string (decimal)	Cumulative volume in quote asset for the bar.
trades	integer	Number of trades in the bar.
taker_buy_volume	string (decimal)	Taker-buy volume in base asset.
taker_buy_quote_volume	string (decimal)	Taker-buy volume in quote asset.
is_closed	boolean	true only on the final push for the bar; otherwise false.

Update frequency

Roughly every 250 ms while the bar is forming, plus a single final push with is_closed: true immediately after the bar closes. If no trade has occurred since the last push, an update may be skipped — never assume a strict cadence.

Reconnection

If the connection drops mid-bar, intermediate updates are lost but the next push (within ~250 ms of reconnect) carries the full cumulative state of the current bar, so consumers are self-healing for in-progress bars.

For closed bars that may have been missed during the disconnect, backfill with GET /v1/market/klines?symbol=...&interval=...&startTime=<last_known_close_time>.