> For the complete documentation index, see [llms.txt](https://developer.barchart.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.barchart.com/getting-started/subscription-types/ohlc.md).

# OHLC

Subscribe to `OHLC` to receive open, high, low, close, and volume data on one-minute wall-clock intervals. Openfeed sends an `ohlc` message only when the market is open and the instrument trades during that interval.

Each message includes the interval's trade count, price-volume total, and start and end timestamps. The following examples show one-minute OHLC data for IBM and MRO.

### OHLC message examples

```protobuf
ohlc {
  marketId: 7407899234554252829
  symbol: "IBM"
  open {
    price: 1373400
  }
  high {
    price: 1373900
  }
  low {
    price: 1373400
  }
  close {
    price: 1373750
  }
  volume: 2340
  priceVolume: 321419.70859999995
  numberTrades: 38
  tradeDate: 20210928
  transactionTime: 1632852360052000000
  openStartTime: 1632852354600000000
  closeEndTime: 1632852355524000000
}

ohlc {
  marketId: 364773838655189731
  symbol: "MRO"
  open {
    price: 138250
  }
  high {
    price: 138300
  }
  low {
    price: 138250
  }
  close {
    price: 138300
  }
  volume: 8974
  priceVolume: 124107.81999999999
  numberTrades: 56
  tradeDate: 20210928
  transactionTime: 1632852360052000000
  openStartTime: 1632852343516000000
  closeEndTime: 1632852358488000000
}
```


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