Direct answer
A “gap” in a forex chart means the plotted price jumps from one level to another with no intermediate points visible. This usually happens because the chart is built from sampled market data (ticks, bid/ask, or aggregated bars) and the charting system may not have a continuous stream for every instant.
How chart gaps happen
Forex markets are highly interconnected but not perfectly continuous for every data series. Common causes include:
- Missing or filtered data: If the feed you use does not provide updates for every moment, the chart cannot draw a smooth line or dense candles. The chart may show the next available price after a pause, which looks like a gap.
- Aggregation into time bars: Many charts display candles/bars (for example, 1-minute or 5-minute). If prices are converted into OHLC bars (open, high, low, close), the chart can appear discontinuous when intermediate values are not stored or when the bar boundaries do not align with the real flow of updates.
- Bid/ask and mid-price choices: Some chart displays track bid, ask, or a derived mid price. Switching between these representations, or using a price series that is derived, can make discontinuities more visible.
- Trading breaks and session effects: Liquidity can change around session transitions. Even when the underlying market is “open,” the number and timing of price updates may vary. Lower update frequency can translate into visible jumps on lower timeframes.
Example checks you can do
Because different chart builds and feeds produce different results, independent checks help you confirm what you’re seeing:
- Compare timeframes: If a gap appears on a 1-minute chart but not on a higher timeframe, it may be related to sampling or bar aggregation rather than a true instantaneous price move.
- Check data density: Look for whether the chart has fewer visible updates around the gap. A sparse area often indicates missing ticks or reduced update frequency.
- Compare the underlying price source: If your platform provides multiple price types (such as bid/ask or mid) or multiple feeds, test whether the gap remains consistent.
- Check your chart settings: Time zone settings and bar construction settings (if available) can shift how candles are formed at boundaries, changing whether a gap looks like a jump.
Limitations and uncertainty
A chart gap does not automatically prove that a large “instantaneous” move occurred; it can also reflect how data is collected, stored, and rendered. Also, what you observe can depend on your platform’s chosen price series, aggregation method, and feed quality. Treat gaps as an output of chart construction and data availability, then verify using timeframe changes and data-source comparisons rather than assuming a single market event.