The short answer
Volume Spread Analysis (VSA) studies the relationship between a bar's volume, its spread (range), and where it closes — to judge whether the effort (volume) matches the result (price move). A divergence — big volume with little movement, or a move on weak volume — is its key tell. It descends from Wyckoff. The crucial caveat: spot forex has no true volume, only tick volume, which weakens VSA on currency pairs.
What VSA is
Volume Spread Analysis looks at three things on every bar: how much volume traded, the spread (the high-to-low range), and where price closed within that range. From the relationship between them, VSA tries to judge whether big, informed players are buying or selling.
It is a direct descendant of the Wyckoff tradition, and its central question is the Wyckoff law of effort versus result.
Effort versus result
The core idea is to compare the effort (volume) with the result (the price move). When they agree — high volume with a wide, strong move — the move looks genuine. When they diverge, it is a warning:
High volume with a narrow range (lots of effort, no progress) can signal absorption and a possible turn. A move on weak volume (result without effort) can signal a weak, unconvincing trend. Climactic volume at an extreme can signal exhaustion.
The forex caveat you must know
Here is the limitation that most VSA tutorials skip. VSA depends on real, accurate volume — and the spot forex market is decentralised. There is no central exchange, so there is no true, centralised volume figure. What your forex chart shows is tick volume: the number of price changes in a period, a proxy for activity, not actual traded volume.
That materially weakens VSA on spot forex pairs compared with centralised, exchange-traded markets like futures or stocks, where real volume exists. It is not that VSA is useless on forex — but you must know you are reading a proxy, not the real thing.
Using VSA honestly
Used well, on the right markets, effort-versus-result is a genuinely useful lens, and volume-price divergences do often precede turns. Used carelessly on spot forex as if the volume were real, it can mislead.
Like every method, it is interpretive and offers no guaranteed edge. Treat a VSA signal as one piece of context alongside structure and risk management, never as a standalone trigger. This is education, not advice.
Frequently Asked Questions
What is Volume Spread Analysis?
A method that studies the relationship between a bar's volume, its range (spread) and its closing position to judge whether informed players are buying or selling. It descends from the Wyckoff tradition.
What does effort versus result mean?
Comparing the volume (effort) with the price move (result). When they agree, the move looks genuine; when they diverge — big volume with little movement, or a move on weak volume — it can warn of a turn or a weak trend.
Can you use VSA on forex?
In a limited way. VSA needs real volume, but spot forex is decentralised and has no true volume — charts show only tick volume, a proxy. That weakens VSA on currency pairs compared with exchange-traded markets like futures.
What is tick volume?
The number of price changes in a period, used as a proxy for activity on spot forex because there is no true centralised volume. It correlates with real activity but is not the same as actual traded volume.
Is VSA a complete trading strategy?
No. It is an interpretive lens with no guaranteed edge, and it is best used as one piece of context alongside structure and risk management. On spot forex, remember you are reading a volume proxy, not real volume.