A fair value gap, or FVG, is the void left on a chart when price moves too fast for every intermediate level to trade. You read it across three consecutive candles: when the extreme of the first and the extreme of the third do not overlap, the untouched space between them is the gap. It is a trace of speed, nothing more: not an order zone, and not a promise that price will come back.
This page covers that single notion. It belongs to the cluster on structured-reading vocabulary, whose index is the smart money glossary, term by term.
What a fair value gap actually describes
Take three consecutive candles in the middle of a bullish impulse. If the high of the first and the low of the third do not overlap, the interval between them was never traded through: that is the fair value gap. The bearish case is symmetrical, comparing the low of the first candle with the high of the third.
So the definition rests on a single condition, mechanical and checkable: no overlap between the first and third candle, produced by a large-range middle candle. The plain-English equivalent is simple: a fast-displacement zone.
How to spot an FVG on a chart
The read happens in three steps.
- Find a large-range middle candle, clearly longer than its neighbours. Without it, there is no gap.
- Compare its two neighbours on their opposing extremes.
- Draw the zone between those two extremes. An FVG is a zone, never a line, and its thickness is the information.
One method point avoids most errors: an FVG is confirmed after the fact, once the third candle closes, never in advance.
Why the market leaves these voids
This is the part the surrounding vocabulary skips, and it can be checked at the source. An FVG is not one participant's signature: it is the trace of a move faster than the order book could refresh.
CME Group, which operates the market where index futures trade, measures this phenomenon itself. Its official documentation describes two complementary mechanisms on the CME Globex platform. Price banding rejects orders outside a band calculated around the last price, so it watches moves that would go too far. Velocity logic watches moves that would go too far, too fast, monitoring extreme prices over a predefined lookback window in very small time increments. When it detects a violation, the futures market involved is temporarily suspended, along with all associated options markets.
In other words, the speed that creates an FVG is a quantity the exchange measures and interrupts when needed. Nothing mysterious in it, and nothing that reveals who bought or sold.
FVG trading: what it adds to a structured read
A fair value gap ranks locations, it does not decide a trade. It answers one precise question: where did the market move without trading?
That narrows the surface of the chart worth watching, and it only has value inside a framework. On its own, a gap is worth any other drawing. It gains weight when other independent reads land in the same place: an impulse origin, a range boundary, a round number. That is the principle behind structured market reading, where a zone only counts when several reads agree on it.
The classic mistake: assuming every gap gets filled
The idea is everywhere: an imbalance ought to be "rebalanced", so price must come back and fill the void. The reasoning sounds solid. It is not.
The reason is mechanical. Every acceleration leaves its gap behind, and a single session produces dozens. In a trending market they stack up in the direction of the move and many are never revisited: that is what a trend looks like. Waiting for the fill therefore means betting against the move in progress, with a drawing as the only justification.
The consequence matters especially at a prop firm, where the daily loss limit leaves no room for a string of entries taken for form's sake. Those limits differ from one firm to the next and should be read at the source: they are gathered on the verified prop firm data page.
What a fair value gap does not tell you
It does not tell you who bought or sold. A void on a chart describes a tempo, not a participant.
It does not tell you which way price will go if it returns. A gap crossed without reaction is itself information: the imbalance that produced it no longer applies.
It does not tell you a price was "unfair". The phrase fair value is a metaphor, not a market mechanism. No exchange rule obliges price to return to where it did not trade.
FVG, imbalance and order block: how they differ
| Term | What defines it | What it measures |
|---|---|---|
| Fair value gap | No overlap between the 1st and 3rd candle | A speed of displacement |
| Imbalance | Buyer/seller imbalance, a generic term | A balance of pressure, with no single numeric definition |
| Order block | Counter-trend zone an impulse departs from | An origin of movement |
The first two terms are used interchangeably almost everywhere, yet only the fair value gap has a reproducible definition. The impulse-origin zone has its own page: the order block. Full definitions are collected in the structured trading glossary.
Frequently asked questions
Is a fair value gap the same as an opening gap?
No. An opening gap is a price jump between two sessions, caused by an interruption in quoting. A fair value gap forms during live quoting, inside a session, without the market stopping. They look alike on a chart but do not share a cause.
Does a fair value gap have to be filled?
No. Nothing requires it, neither market mechanics nor any exchange rule. In an established trend, gaps accumulate in the direction of the move and many are never revisited.
Does an FVG prove institutions were involved?
No. It describes the speed of a move, not its author. That speed is in fact a quantity CME tracks itself, and its velocity logic can temporarily suspend a market that goes too far, too fast.
The method that ties these reads into an execution framework is presented on the Prop System page.
Ephore Market doctrine article, published on 18 August 2026. The price banding and velocity logic mechanisms were reviewed on 18 August 2026 on the official CME Group website. These market parameters can change: always check the official source before relying on them.
Futures trading involves substantial risk of capital loss. This article is educational and does not constitute investment advice.