The Force Index: Price Change Multiplied by Volume

Elder’s Force Index is one of the few classic oscillators with a genuinely clear idea behind it: a move matters more when a lot of trading happened during it. The problem is that on most retail forex platforms the volume input is not volume at all.

Force Index at a glance

What it is and why it works

The raw calculation is a single line: take this bar’s close, subtract the previous bar’s close, and multiply the result by this bar’s volume. A bar that closed 10 points higher on twice the usual volume scores twice as much as one that closed 10 points higher on normal volume. That is the whole mechanism, and the intuition is sound; the same price move made with more participation is a stronger statement about who is in control.

The raw series is far too jagged to read, so it is almost always smoothed with an exponential moving average. Alexander Elder, who created it, proposed two settings for two different jobs. A 2-period EMA leaves a fast, noisy line used to time entries within an established trend. A 13-period EMA produces a much smoother line used to judge whether the trend itself is being supported by participation. They are effectively two different indicators sharing a name, and mixing them up is the most common reason the tool confuses people.

Now the part that most descriptions of the Force Index leave out. In spot forex there is no central exchange and therefore no real volume figure. What MetaTrader shows you by default is tick volume: the number of times the price changed during the bar. That is a proxy for activity, and a reasonable one at liquid times, but it is not the number of contracts or lots traded. It also comes from your broker’s own feed, so two brokers can produce visibly different Force Index readings on the same pair at the same moment. On exchange-traded instruments (index futures, commodity futures, shares) MT5 can show real volume, and there the indicator is measuring what it claims to measure.

On redundancy, be clear-eyed. The price-change half of the formula is exactly what Momentum and Rate of Change measure, and the volume half is what OBV accumulates. Force Index is essentially momentum weighted by participation. If you already run OBV and an oscillator built on price change, adding Force Index does not give you a third opinion; it gives you a product of the two you already have. Its genuine contribution is that it keeps the size of the price move, which OBV throws away by using only the sign.

How to trade it, step by step

1. Add it and choose your job first. In MT5 go to Insert → Indicators → Oscillators → Force Index. Decide before you set the period whether you want a trend-health read or an entry-timing read, because the two use different settings and cannot be done well by one line.
2. For trend health, set the period to 13. This produces a slow line. Read only two things from it: which side of zero it is on, and whether it is making higher or lower extremes as price does. Sustained readings above zero say buyers have been doing the work; sustained readings below zero say sellers have.
3. For entry timing inside a trend, set the period to 2 on a separate instance. The 2-period line whips either side of zero constantly. Its only legitimate use is this: in an established uptrend, a dip in the fast line below zero marks a pause where buyers stepped back, and a trade in the direction of the trend can be timed there. Never use it to pick direction, direction comes from the 13 line or from structure.
4. Check what your volume input actually is. Open the indicator’s properties and look at Applied Volume. On spot forex this will be Tick, meaning price-change counts, not traded size. On an instrument where your broker provides Real volume, switch to it. If you do not know which you are looking at, you do not know what the indicator is telling you.
5. Read spikes, not levels. The absolute value has no meaning; it is price units multiplied by a volume count, so it changes if you switch instrument, timeframe or broker. What is readable is a spike far outside the recent range of the line, which marks a bar where an unusually large move met unusually heavy participation. That is worth noticing wherever it lands.
6. Look for divergence at the extremes only. If price makes a new high but the 13-period Force Index makes a lower high, the new high was achieved with less force behind it. Treat that as a reason to tighten management on an existing position, not as a reason to enter the opposite side. Divergence can persist for a long time in a strong trend.
7. Ignore it outside active hours. Force Index is a volume-weighted tool and thin conditions produce readings dominated by the price term with almost nothing behind it. On FX that means the main sessions; on index and commodity instruments it means cash hours rather than the overnight session.
8. Do not run it alongside OBV and a momentum oscillator and call it agreement. Force Index is built from the same two ingredients. If you want a second opinion, take it from structure, from a higher timeframe, or from something that can genuinely disagree.

Size every one of those entries with the position size calculator and check the trade is worth taking with the risk/reward calculator before you commit.

The conditions it needs

Instruments with real, exchange-reported volume

This is where the indicator does what it claims. Index futures, commodity futures and shares report actual traded size, so a large Force Index reading really does mean a big move on heavy participation. On these instruments it is one of the more informative volume tools available.

Established trends, for timing rather than direction

The 2-period version has a narrow and real use: finding the shallow pauses inside a trend you have already identified. When the trend is genuine and the pullbacks are orderly, a dip in the fast line marks the moment participation paused, which is usually a better place to join than the point where price looks strongest.

Confirming or questioning a breakout

A break of a structural level accompanied by a Force Index spike well outside its recent range means the move was made with unusual participation. A break accompanied by an ordinary reading means price crossed a line and nothing changed. That distinction is genuinely difficult to see on the price chart alone.

Active sessions on liquid instruments

Tick volume is a decent activity proxy when there is plenty of activity to count. During the London–New York overlap on a major pair, tick counts track real flow closely enough to be useful. In the Asian session on a cross, they do not.

When it fails

• Tick volume is not volume. On spot forex the indicator is multiplying price change by the number of price updates your broker sent. That is a proxy for activity, not a measure of size, and it varies between brokers on the same pair. Any conclusion that depends on the magnitude being real is unsafe on FX.
• The scale is meaningless in isolation. A reading of 45,000 tells you nothing without knowing the instrument, the timeframe and the recent range of the line itself. Traders who set fixed thresholds on the Force Index are setting thresholds on units that change whenever anything else does.
• The 2-period version is noise if used for direction. It crosses zero constantly by design. Trading every cross produces a stream of trades with no edge and heavy costs. It was only ever intended as a timing tool inside a trend already established by something else.
• It is redundant with what most traders already have. Price change is momentum; volume accumulation is OBV. If both are already on the chart, Force Index is their product wearing a different name, and three lines that always agree feel like confluence while providing none.
• Gaps and rollovers produce false spikes. The formula uses the change from the previous close, so a weekend gap or a futures contract roll registers as an enormous move. On volume that is often low at the same moment, this can look either dramatic or invisible, and neither reading reflects anything a trader can act on.
• Divergence is not a reversal signal. Force Index divergence tells you the latest push had less behind it than the last one. In a strong trend that can be true for weeks while price continues. Using it to enter counter-trend is the fastest way to lose money with this indicator.

Markets it is most informative on

• GER40 (DAX): Real participation data during cash hours makes the volume half of the formula genuinely informative.
• Gold (XAU/USD): Sharp participation surges around London and New York opens show up clearly as Force Index spikes.
• NAS100 (Nasdaq): Fast, high-participation moves where the difference between a supported break and an empty one matters most.
• Oil (WTI Crude): Inventory-driven activity spikes are exactly the kind of event the indicator is designed to register.

For different levels of experience

If you are brand new

The idea is simple enough to picture. If price rose today, that is one thing. If price rose today and far more trading than usual took place, that is a stronger statement. The Force Index puts a number on the combination.

Set the period to 13 and use it for one purpose only: is the line above zero or below it? Above zero, buyers have been doing more of the work recently. Below zero, sellers have. That is a useful sanity check before you take a trade, because a lot of losing trades are bets against whoever is currently doing the work.

Two things to know before you trust it. First, on forex your platform is not showing real volume; it is counting how many times the price ticked, which is a rough stand-in. Second, the numbers on the scale mean nothing on their own; only the shape and the side of zero are readable. Do not go looking for a level that means “buy” because there is not one.

If your results are inconsistent

The intermediate mistake here is running the 2-period and treating its zero crosses as signals. It crosses constantly. Elder’s design intended the 13 to establish whether the trend is being supported and the 2 to time an entry within a direction you had already chosen. Using the fast line for direction inverts the whole method.

The second adjustment is to stop reading Force Index as an independent confirmation. Look at your chart honestly: if you have OBV, a momentum oscillator and Force Index, you have three views of price change and volume, and they will agree almost all the time because they are built from the same two numbers. That agreement feels like evidence and is not. Drop two of them and put the attention into structure or into the session you are trading.

Finally, get in the habit of checking Applied Volume in the properties dialog. If you trade both FX and index CFDs, the same indicator is measuring two genuinely different things on the two charts, and the conclusions you can safely draw differ accordingly.

If you are experienced

Force Index is a first difference of price weighted by contemporaneous volume, effectively a crude order-flow imbalance proxy that assumes signed participation can be inferred from the sign of the close-to-close change. On instruments with real reported volume that assumption is workable at bar granularity. On tick-volume FX it degrades into a broker-specific activity index, and the magnitude carries no cross-venue meaning at all.

The informative content is concentrated in the tails. Normalising the smoothed series by its own rolling standard deviation gives a comparable z-score, and the z-scored extremes (not the level, not the zero cross) are where the series adds anything beyond what a volume-blind momentum measure already tells you. Those extremes cluster at genuine initiative moves and at capitulation, which is the same place a volume profile read is most valuable, and the two together are a stronger combination than either with another price-derived oscillator.

Two structural cautions. The close-to-close term makes the series discontinuous across gaps and futures rolls, so any systematic use needs explicit handling of those bars rather than letting a spike propagate through the EMA. And because the volume term is unbounded and heavy-tailed, a single abnormal bar dominates a 13-period EMA for a considerable stretch afterwards, which quietly turns a trend-health indicator into a record of one event.

Risk management for this strategy

Force Index gives no stop level and no target, so it cannot size a trade. What it can do is tell you when your assumptions about liquidity are wrong, and that has direct risk consequences.

A sustained collapse in the volume term means fewer participants, which in practice means worse fills, wider spreads and a greater chance that your stop is reached by a thin move rather than a real one. When the Force Index has been flat near zero for an extended period, the correct response is a smaller position or none at all, not a tighter stop.

The opposite state carries its own risk. An extreme spike marks a bar where a great deal happened quickly, and the bars that follow such a spike frequently have unusually wide ranges. Entering immediately after one with a stop sized for normal conditions is a common way to be stopped out of a correct idea. Recalculate the size from the current bar range rather than from last week’s using the position size calculator.

Where Market Structure Pro fits

The judgement Force Index is supposed to help with (is there real participation behind this move, or is it price drifting through a level with nobody behind it?) is one of the hardest to make consistently, and it is made much harder in forex where the volume figure is a proxy from your own broker.

Market Structure Pro approaches the same question from several directions at once. It fuses 27 tools into a single TRADE, TRANSITION or NO TRADE verdict with a confidence percentage and a grade, so participation is weighed against structure, session and spread rather than read from one line in isolation. Its session awareness matters here in particular: a Force Index reading during the Asian session on a European cross and the same reading during the London–New York overlap describe completely different market states, and MSP grades the setup for the conditions it is actually in.

The chop filter covers the other failure mode. Force Index oscillating shallowly around zero is exactly what a directionless market looks like, and that is the state MSP is built to label NO TRADE rather than leaving you to interpret an ambiguous line. Because the verdict locks on the closed bar and does not repaint, what you saw when you decided is what you can review afterwards.

Frequently asked questions

What does the Force Index measure?

It multiplies the change in price from the previous close by the volume of that bar, then smooths the result with an exponential moving average. The idea is that a price move backed by heavy trading is a stronger statement than the same move on light trading, so the indicator combines size of move and participation into one number.

What are the best Force Index settings?

Alexander Elder proposed two, for two different jobs. A 13-period exponential smoothing gives a slow line used to judge whether a trend is being supported by participation, while a 2-period gives a fast line used only to time entries inside a trend that has already been identified. Using the fast line to pick direction is the most common misuse.

Does the Force Index work in forex?

Partly. The price half of the formula works normally, but spot forex has no central exchange and therefore no true volume, so MetaTrader substitutes tick volume, which counts how many times the price changed. That is a reasonable activity proxy during liquid sessions but it is not traded size, and it differs between brokers on the same pair.

Is the Force Index in MetaTrader 5 by default?

Yes. It ships as a standard indicator and is found under Insert, then Indicators, then Oscillators. In its properties you can set the period, the smoothing method and, importantly, whether Applied Volume uses tick volume or real volume where your broker provides it.

What is the difference between the Force Index and OBV?

On Balance Volume adds or subtracts the whole bar's volume depending only on whether the close was up or down, so it ignores how far price moved. The Force Index keeps that distance and multiplies by volume, so a large move counts for more than a small one. They are close relatives and running both adds little.

What does a Force Index zero cross mean?

It means the net volume-weighted price change over the smoothing window has flipped sign. On the 13-period version that is a slow, reasonably meaningful shift in which side has been doing the work. On the 2-period version it happens constantly and carries almost no information on its own.

Is Force Index divergence reliable?

It tells you that the most recent push into a new price extreme was achieved with less force behind it than the previous one, which is genuine information. It is not a reversal signal, because divergence can persist for a long time in a strong trend. It is better used to tighten management of an existing position than to enter the opposite side.

Why do Force Index values look completely different on two charts?

Because the scale is price change multiplied by volume, so it depends on the instrument's price units, the timeframe, and how much volume the broker reports. There is no normalised range, and no fixed level means anything. Only the sign, the shape and spikes relative to the line's own recent behaviour are readable.

Related reading

• On Balance Volume: The volume half of the same idea, using only the direction of the close.
• Money Flow Index: A bounded volume-weighted oscillator: a more comparable alternative.
• Momentum: The price half of the Force Index formula, without any volume weighting.
• Volume Profile Trading: Where volume is read by price level rather than by bar: a genuinely different view.