Candles(OHLCV)

Candle Real-Time Stream Transmission Guide

Data Transmission Interval

The real-time stream transmission interval for candle data is 1 second.

Data Generation Information

Candles are generated only when trades occur during the given time period and the candle data changes compared to the previous candle. Even if 1 second passes, if no trades occur, no real-time candle data stream is transmitted.

Additionally, if the requested candle data for the specified interval has not yet been generated at the time of the request, the data for the previous time interval is sent first.

The same candle_date_time data may be transmitted multiple times.

Due to the nature of real-time candle streams handling requests of various time units, it is difficult to guarantee a perfect transmission interval, and candle data for the same time period may be sent multiple times depending on the trade timing. The most recently received data is the latest; please refer to the candle_date_time field to update the values before use.

WebSocket Endpoint

Type	Endpoint
Public	`wss://{region}-api.upbit.com/websocket/v1`

Use the endpoint for your region.

Region	Endpoint
Singapore	`wss://sg-api.upbit.com/websocket/v1`
Indonesia	`wss://id-api.upbit.com/websocket/v1`
Thailand	`wss://th-api.upbit.com/websocket/v1`

Request Message Format

To request announcement data, after establishing a WebSocket connection, create a JSON Object with the structure below and include it as a Data Type Object in the request message.

For the complete WebSocket request message specification, including the Ticket and Format Objects, refer to the WebSocket Usage and Error Guide.

Field Name	Type	Description	Required	Default
type	String	Data type to receive. Set to `candle.`{unit} to receive candle data.	Required
codes	List:String	List of trading pairs to receive. Must be requested in uppercase.	Required
is_only_snapshot	Boolean	Provide snapshot data only	Optional	`false`
is_only_realtime	Boolean	Provide real-time data only	Optional	`false`
format	String	Data format to receive. `DEFAULT`: Default format. `SIMPLE`: Simplified format with abbreviated field names. `JSON_LIST`: List format. `SIMPLE_LIST`: List format with abbreviated field names.	Required

Custom function for Orderbook Unit quantity is added
You can adjust the quantity of Orderbook Units only for orderbook-type packets. Please input the market code and unit quantity as follows.
Format: {code}.{count}
Example: SGD-BTC.5, SGD-ETH.5
Supported values for count: 1, 5, 15, 30
If an unsupported value is specified, it defaults to 30.

Subscription Data Specification

When a new announcement is published or an existing announcement is updated, real-time stream data is returned as follows.

Field Name	Abbreviation	Description	Type	Value Example
type	ty	Type	String	`candle.1s`: 1-second candle `candle.1m`: 1-minute candle `candle.3m`: 3-minute candle `candle.5m`: 5-minute candle `candle.10m`: 10-minute candle `candle.15m`: 15-minute candle `candle.30m`: 30-minute candle `candle.60m`: 60-minute candle `candle.240m`: 240-minute candle
code	cd	Pair code (e.g., SGD-BTC)	String
candle_date_time_utc	cdttmu	Candle base time (UTC) Format: `yyyy-MM-dd'T'HH:mm:ss`	String
opening_price	op	Opening price	Double
high_price	hp	High price	Double
low_price	lp	Low price	Double
trade_price	tp	Closing price	Double
candle_acc_trade_volume	catv	Accumulated trade volume	Double
candle_acc_trade_price	catp	Accumulated trade amount	Double
timestamp	tms	Timestamp (ms)	Long
stream_type	st	Stream type	String	`SNAPSHOT`: Snapshot `REALTIME`: Real-time

Examples

Subscription Request Example

[
  {
    "ticket": "0e66c0ac-7e13-43ef-91fb-2a87c2956c49"
  },
  {
    "type": "candle.1s",
    "codes": ["SGD-BTC","SGD-ETH"]
  },
  {
    "format": "DEFAULT"
  }
]

Subscription Data Example

{
  "type": "candle.1s",
  "code": "SGD-BTC",
  "candle_date_time_utc": "2025-01-02T04:41:51",
  "opening_price": 130155.0000000,
  "high_price": 130155.0000000,
  "low_price": 130155.0000000,
  "trade_price": 130155.0000000,
  "candle_acc_trade_volume": 0.00003473,
  "candle_acc_trade_price": 4.520283150000000,
  "timestamp": 1735792911165,
  "stream_type": "REALTIME"
}
{
  "type": "candle.1s",
  "code": "SGD-ETH",
  "candle_date_time_utc": "2025-01-02T04:42:59",
  "opening_price": 4654.0000000,
  "high_price": 4654.0000000,
  "low_price": 4654.0000000,
  "trade_price": 4654.0000000,
  "candle_acc_trade_volume": 0.00086015,
  "candle_acc_trade_price": 4.003138100000000,
  "timestamp": 1735792979607,
  "stream_type": "REALTIME"
}

Error Information

If an error occurs after establishing a WebSocket connection and sending a request, the response is returned in the following JSON format.

{
  "error": {
    "name": "ERROR_CODE",
    "message": "ERROR_MESSAGE"
  }
}

The main error codes that may be returned are listed below.

`error.name`	Reason	Recommended Action
`INVALID_AUTH`	Missing authentication information or authentication token verification failure	When using a Private WebSocket endpoint, make sure you are connected to the correct endpoint and that the `Authorization` header contains a valid authentication token.
`WRONG_FORMAT`	Invalid request message format	Make sure the request message follows the WebSocket request format. Check the Object structure as well as the type and value of each field.
`NO_TICKET`	Missing `ticket` field	Make sure the request message includes a Ticket Object and the `ticket` field.
`NO_TYPE`	Missing `type` field	Make sure the Data Type Object includes the `type` field and specify the data type to subscribe to.
`NO_CODES`	Missing `codes` field	Check whether the subscribed data type requires the `codes` field and specify the trading pair codes to receive.
`INVALID_PARAM`	Missing required request field or unsupported value	Make sure all required fields are included and that each field contains a supported value.
`Too Many Requests`	Request rate limit exceeded	Wait until another request can be made, then retry. Refer to the Rate Limits section for details.
`I'm a teapot`	Requests are temporarily restricted due to repeated `Too Many Requests` errors	Check the restriction period included in the response and retry after the specified time has passed.

Rate Limits

APIs are grouped into Rate Limit groups. APIs within the same group share the same per-second request limit.

The maximum number of requests allowed per Rate Limit group may change after prior notice according to service policy, and additional restrictions may be applied depending on service conditions. For details, refer to Rate Limits.

Rate Limit Group	Policy	Applied By
`websocket-connect`	Up to 5 connections per second	IP
`websocket-message`	Up to 5 messages per second and 100 messages per minute	Connection

Managing WebSocket Rate Limits
Unlike REST API responses, WebSocket does not provide the number of remaining requests. Clients should track the number of WebSocket connection attempts and data request messages they send to ensure compliance with the applicable rate limits. If a rate limit is reached, wait for an appropriate period before sending another request..