Public

Candlestick Channel

Description

Get the candlestick data of the product

When there are transactions in the K-line channel, data is pushed once per second.
When there are no transactions, data is pushed once at the specified time granularity.

Push logic adjustment

Effective in demo trading on November 4, 2026, and expected in live trading on November 17, 2026: after a successful subscription, this channel will no longer push snapshot data (action=snapshot); only real-time incremental data (action=update) will be pushed. Before the adjustment takes effect, the first push after subscription is a snapshot of recent data. To obtain historical data, please use the corresponding REST API.

Notes for Reality stock (rtoken) symbol subscription

Only the market candlestick type is supported.
Only the 1m, 5m, 15m, 1H, 4H, 1D intervals are supported.
For the 1m interval, volume and turnover are not included in the push data.


Code
{
    "op": "subscribe",
    "args": [
        {
            "instType": "spot",
            "topic": "kline",
            "symbol": "BTCUSDT",
            "interval": "1D"
        }
    ]
}

Request Parameters

Parameter	Type	Required	Description
op	String	Yes	Action `subscribe` Subscribe `unsubscribe` Unsubscribe
args	List<Object>	Yes	Subscribed channel
> instType	String	Yes	Product type `spot` Spot trading `usdt-futures` USDT futures `coin-futures` Coin-M futures `usdc-futures` USDC futures
> topic	String	Yes	Topic `kline` K-line channel
> symbol	String	Yes	Symbol name e.g., `BTCUSDT`
> interval	String	Yes	Interval `1m`, `3m`,`5m`, `15m`, `30m`, `1H`, `4H`,`6H`, `12H`, `1D`


Code
{
  "event": "subscribe",
  "arg": {
    "instType": "spot",
    "topic": "kline",
    "symbol": "BTCUSDT",
    "interval": "1D"
  },
  "connId": "xxxxxxxxxx"
}

Response Parameters

Parameters	Type	Description
event	String	Action `subscribe` Subscribe `unsubscribe` Unsubscribe `error` Parameter error
arg	Object	Subscribed channel
> instType	String	Product type `spot` Spot trading `usdt-futures` USDT futures `coin-futures` Coin-M futures `usdc-futures` USDC futures
> topic	String	Topic `kline` K-line channel
> symbol	String	Symbol name e.g., `BTCUSDT`
> interval	String	Interval
code	String	Error code
msg	String	Error message
connId	String	Connection ID


Code
{
  "data": [
    {
      "volume": "0.423",
      "high": "400005",
      "low": "276670",
      "start": "1710518400000",
      "close": "400005",
      "turnover": "148190.38375",
      "open": "276670"
    }
  ],
  "arg": {
    "instType": "spot",
    "symbol": "BTCUSDT",
    "topic": "kline",
    "interval": "1D"
  },
  "action": "update",
  "ts": 1736370735556
}

Push Parameters

Parameters	Type	Description
arg	Object	Subscribed channel
> instType	String	Product type `spot` Spot trading `usdt-futures` USDT futures `coin-futures` Coin-M futures `usdc-futures` USDC futures
> topic	String	Topic `kline`
> symbol	String	Symbol name
action	String	Push data action `snapshot` Full data `update` Incremental data After the push logic adjustment takes effect, only `update` is pushed
data	List<Object>	Subscribed data
> start	String	The timestamp that the system generated the data A Unix timestamp in milliseconds
> open	String	Open price
> close	String	Close price
> high	String	Highest price
> low	String	Lowest price
> volume	String	Trade Volume The unit is base coin
> turnover	String	Turnover The unit is quote coin

Tickers Channel Depth Channel

Parameter

Type

Required

Description

String

Yes

Action
subscribe Subscribe
unsubscribe Unsubscribe

args

List<Object>

Yes

Subscribed channel

> instType

String

Yes

Product type
spot Spot trading
usdt-futures USDT futures
coin-futures Coin-M futures
usdc-futures USDC futures

> topic

String

Yes

Topic
kline K-line channel

> symbol

String

Yes

Symbol name
e.g., BTCUSDT

> interval

String

Yes

Interval
1m, 3m,5m, 15m, 30m, 1H, 4H,6H, 12H, 1D

Parameters

Type

Description

event

String

Action
subscribe Subscribe
unsubscribe Unsubscribe
error Parameter error

arg

Object

Subscribed channel

> instType

String

Product type
spot Spot trading
usdt-futures USDT futures
coin-futures Coin-M futures
usdc-futures USDC futures

> topic

String

Topic
kline K-line channel

> symbol

String

Symbol name
e.g., BTCUSDT

> interval

String

Interval

code

String

Error code

msg

String

Error message

connId

String

Connection ID

{
  "data": [
    {
      "volume": "0.423",
      "high": "400005",
      "low": "276670",
      "start": "1710518400000",
      "close": "400005",
      "turnover": "148190.38375",
      "open": "276670"
    }
  ],
  "arg": {
    "instType": "spot",
    "symbol": "BTCUSDT",
    "topic": "kline",
    "interval": "1D"
  },
  "action": "update",
  "ts": 1736370735556
}

Parameters

Type

Description

arg

Object

Subscribed channel

> instType

String

Product type
spot Spot trading
usdt-futures USDT futures
coin-futures Coin-M futures
usdc-futures USDC futures

> topic

String

Topic
kline

> symbol

String

Symbol name

action

String

Push data action
snapshot Full data
update Incremental data
After the push logic adjustment takes effect, only update is pushed

data

List<Object>

Subscribed data

> start

String

The timestamp that the system generated the data
A Unix timestamp in milliseconds

> open

String

Open price

> close

String

Close price

> high

String

Highest price

> low

String

Lowest price

> volume

String

Trade Volume
The unit is base coin

> turnover

String

Turnover
The unit is quote coin