Why do candlestick charts differ between trading platforms?

Different platforms often use different data vendors or aggregation methods for constructing candles, which can create small but visible differences, even when both are technically showing the same underlying stock’s price action. Some of this comes from data feed timing differences (real-time versus slightly delayed), some from how each platform’s charting engine handles gaps, illiquid periods with few trades, or after-hours and pre-open session data. The choice of exchange also matters if a stock is dual-listed on both NSE and BSE, since price and volume can differ slightly between the two exchanges at any given moment, and if one platform defaults to NSE data while another defaults to BSE, the candles will reflect genuinely different underlying trades, not just a rendering difference. For serious technical analysis, you stick to one platform consistently rather than comparing candle-by-candle across two different charting tools, since small discrepancies are normal and don’t necessarily indicate an error on either platform’s part.