OHLC

OHLC stands for Open, High, Low, Close — the four prices that summarize trading activity within a single time period on a chart. The open is the first traded price of the period, the high and low are the extremes reached, and the close is the last traded price before the next period begins. These four numbers are the raw data behind both candlestick charts and OHLC bar charts, and most technical indicators are calculated from them, usually from the close.

For example, a daily OHLC reading for Ethereum might be: open $3,000, high $3,150, low $2,940, close $3,100. From those numbers alone you can tell the day ended higher than it started, buyers pushed price about 5% above the open at the peak, and sellers briefly drove it below the open.

Because crypto markets trade continuously, the daily open and close are conventions rather than natural boundaries — most platforms use 00:00 UTC, so the same day can look slightly different across data providers. A common misconception is that OHLC data captures everything; it omits how price moved within the period and how much volume traded at each level, which is why some traders drop to shorter timeframes for detail.