A candle summarizes Open, High, Low and Close for a chosen period. Comparable classification requires the same data type, timeframe, precise geometric condition and any preceding-trend context.
StockCharts defines the body between Open and Close and the shadows extending toward High and Low. Do not confuse the full High − Low range with body size. [1]
StockCharts illustrates different body and shadow sizes. Set tolerances and ratios in advance for your test; labels such as long shadow or small body alone provide no reproducible numerical threshold. [1]
StockCharts interprets the same shapes in the context of preceding advances or declines. Separate geometric recognition from interpretation of a possible reversal; Doji alone, for example, is neutral. [1]
TradingView explains that a live candle's High, Low and Close change. A rule intended for closed candles must not present a provisional shape as a definitively completed pattern. [2]
TradingView must assume the intrabar movement sequence in historical simulation. OHLC alone therefore does not establish whether High occurred before Low; that can affect simulated entries and exits. [4]
TradingView states that Heikin-Ashi calculates synthetic OHLC. Its shape and prices are not a direct record of actual market OHLC; do not confuse the results with a rule tested on ordinary candles. [3]
If a rule waits for another candle, the result becomes known only afterward. TradingView warns about lookahead bias: a test cannot assign future confirmation to the original pattern's time. [4]
TradingView describes overfitting, selection bias, costs and Slippage. Performance evaluation must include all cases and execution; a collection of attractive candles does not prove a profitable strategy. [4]
Decomposing one candle without a forecast
A hypothetical candle has Open = 100000, High = 103000, Low = 99000 and Close = 102000 USD/BTC. Its body measures 102000 − 100000 = 2000 USD/BTC. The upper shadow is 103000 − 102000 = 1000 USD/BTC, the lower shadow 100000 − 99000 = 1000 USD/BTC and the range 103000 − 99000 = 4000 USD/BTC. The body occupies 2000 / 4000 = 0.5 of the range. These numbers tell us neither whether High or Low occurred first nor whether the next price will rise.
For the clearest picture, read this entry together with OHLCV, Doji, Engulfing Pattern, Timeframe, Slippage, Backtesting. The reverse links also lead from Candlestick chart, Doji, Engulfing Pattern, Hammer and Shooting Star.
01Does a rising body guarantee that the next candle rises?+
No. Close above Open describes the completed period. That relationship does not guarantee the next move.
02Is naming a familiar pattern enough for a test?+
No. You need precise shape, context and confirmation rules, as well as separate entry, exit and cost conditions.