MFI barely fires on forex: 240 settings tested
240 MFI settings backtested on USD/JPY across 2025 and 2024: on four-hour bars 137 took fewer than ten trades a year, and the textbook setting placed 1st then 117th.
MFI, the Money Flow Index, is usually introduced as "RSI weighted by volume." Below 20 is oversold, above 80 overbought — the same reading as RSI, with volume behind it.
I tested it on USD/JPY across the whole of 2025: six periods × five entry levels × four exit levels × two directions, 240 settings, on three timeframes, then the same 240 again on 2024.
The first finding came before any question of performance. On forex's higher timeframes, this indicator hardly trades at all.
On four-hour bars, 48 of the 240 settings took no trades in a year and 137 took fewer than ten. On hourly bars, 20 took none and 81 took fewer than ten. Before arguing about the best period, there is the question of whether there is a sample to argue about.
Why it stays quiet
For MFI to drop below 20, the volume-weighted total of down bars has to dominate the up bars across the whole lookback. That is a narrower condition than RSI's, so the extremes are reached less often.
Raise the timeframe and there are fewer bars for the condition to occur in. A year of four-hour bars is about 1,610 candles. Choose period 28 with a level of 10 there and going a whole year without the condition lining up is an ordinary outcome, not a freak one.
| Timeframe | Median trades a year (of 240 settings) | Settings with 0 trades | Settings under 10 trades |
|---|---|---|---|
| 15-minute | 80 | 8 / 240 | 54 / 240 |
| 1-hour | 23 | 20 / 240 | 81 / 240 |
| 4-hour | 5 | 48 / 240 | 137 / 240 |
(2025, long and short sides combined.)
About that volume
One more thing worth stating before the results.
MFI's calculation takes volume as an input. In equities that volume is consolidated at an exchange and comes close to meaning "how much money moved." Forex has no such consolidated figure. What appears on a chart is what a single source observed.
So when MFI is used on forex, the weighting that gives the indicator its name rests on weaker ground than the textbook description implies. Every number below sits on that footing.
Adding MFI to a chart
| Platform | How to add it |
|---|---|
| MT4 / MT5 | Built in — Navigator, Oscillators, Money Flow Index |
| TradingView | In the indicator list as "Money Flow Index" |
| Browser (Formiq) | In the indicator list, with an adjustable period |
How this was measured
The rule is directional: "below 20" can only be a buy and "above 80" can only be a sell, so the two sides are separate systems.
| Item | Value |
|---|---|
| Pair | USD/JPY |
| Period | 2025-01-01 to 2025-12-31 (2024 run identically for comparison) |
| Timeframes | 15-minute / 1-hour / 4-hour |
| Bars tested | 6,226 hourly bars in 2025; 24,903 on 15-minute, 1,610 on 4-hour |
| Long side | Buy when MFI falls below the entry level (10–30), close when it rises above the exit level (50–90) |
| Short side | The mirror (sell at 70–90, close at 10–50) |
| Stops and targets | None |
| Costs | 0.3 pip spread, zero slippage, 0.1 lot |
| Combinations | 6 periods (7–40) × 5 entry levels × 4 exit levels × 2 directions = 240, per timeframe and per year |
| Method | Executed in Formiq's backtester; pips recomputed from each trade's fill prices |
What happened to the textbook setting
Period 14, buy below 20, close above 80 — the version everyone quotes.
| 2025 | 2024 | |
|---|---|---|
| 15-minute long | 145 trades, 61.38% win, +1,379.1 pips (1st of 120) | 113 trades, 62.83% win, −654.2 pips (117th) |
| 15-minute short | 146 trades, 60.27% win, +1,426.3 pips (1st) | 113 trades, 50.44% win, −2,236.8 pips (113th) |
| 1-hour long | 37 trades, 56.76% win, −108.0 pips (68th) | 27 trades, 77.78% win, +245.4 pips (41st) |
| 4-hour long | 9 trades, 77.78% win, +570.4 pips (27th) | 6 trades, 50.00% win, −277.0 pips (104th) |
Best of 120 in 2025. 117th of 120 in 2024.
Each dot is one of the 120 long-side settings: 2024 across, 2025 up. The red dot is the textbook setting, sitting top-left — heavily negative one year, heavily positive the next.
Across the whole cloud there is no slope in either direction. The rank correlation is 0.00 — the most complete disconnect between two years in this series of tests.
| Timeframe · side | Rank correlation, 2024 ↔ 2025 |
|---|---|
| 15-minute long | +0.00 |
| 15-minute short | −0.248 |
| 1-hour long | +0.280 |
| 1-hour short | +0.021 |
| 4-hour long | +0.199 |
| 4-hour short | −0.247 |
By timeframe and direction
| Timeframe · side | Profitable 2025 | 2025 median | Profitable 2024 | 2024 median | Both years |
|---|---|---|---|---|---|
| 15-minute long | 74 / 120 | +35 pips | 77 / 120 | +142 pips | 50 / 120 |
| 15-minute short | 80 / 120 | +97 pips | 11 / 120 | −1,195 pips | 7 / 120 |
| 1-hour long | 46 / 120 | −31 pips | 56 / 120 | 0 pips | 31 / 120 |
| 1-hour short | 37 / 120 | −186 pips | 5 / 120 | −1,214 pips | 3 / 120 |
| 4-hour long | 77 / 120 | +156 pips | 65 / 120 | +84 pips | 53 / 120 |
| 4-hour short | 64 / 120 | +33 pips | 20 / 120 | −603 pips | 7 / 120 |
The short side breaks in 2024 on all three timeframes. USD/JPY rose 1,632 pips that year, and selling "overbought" through that does not survive. The same thing happened to Williams %R.
The long side hovers around zero: +35 and +142 pips on 15-minute, −31 and 0 on hourly. Neither winning nor losing much is what this indicator did on its own.
Only the settings with a real sample
Restricting to settings that took at least 20 trades (hourly long side, 2025, 65 settings):
- Win rate range: 47.5% to 72.73%
- Median net: −304 pips
- Profitable: 13 of 65
High win rates, no result — the same structure Williams %R showed, and for the same reason: a counter-trend exit rule caps the upside while leaving the downside open.
Note also that including the near-empty settings puts rows with 0% and 100% win rates into the table. A win rate computed from one or two trades a year is not a win rate in any useful sense. Read every win rate here next to its trade count.
What this test supports
- On higher timeframes it does not trade enough to judge. 137 of 240 four-hour settings under ten trades a year; 48 with none
- The textbook setting reverses between years. 1st of 120 in 2025, 117th in 2024, with a rank correlation of 0.00
- The short side breaks in a rising market. 11, 5 and 20 of 120 profitable in 2024
- The long side goes nowhere in particular. Medians sit on top of zero
- The volume premise is weak on forex. There is no consolidated volume to weight by
Using MFI as a standalone signal on forex is not supported by these numbers. On a timeframe where it fires often enough, and alongside a separate judgement about direction, is as far as this goes.
The same method applied to Williams %R, QQE, Aroon, RVI and Supertrend.
Limits of this test
- One pair, two years
- 2024 rose 1,632 pips; 2025 finished 56 pips lower inside a 1,900-pip range. For a counter-trend indicator that difference is decisive
- Forex volume is not a market-wide figure. MFI's calculation rests on it
- Entries and exits both fill at bar closes
- Settings with very few trades are included in the aggregates; the figures excluding them are given separately above
- Volatility varies by hour of the day
Questions people ask
- What are the best MFI settings?
- This test did not find any. On 15-minute bars the textbook long setup — period 14, buy below 20, close above 80 — ranked 1st of 120 in 2025 (+1,379.1 pips) and 117th in 2024 (−654.2 pips). The rank correlation between the two years for that whole cell is 0.00.
- Does MFI work on forex?
- Check whether it fires before asking whether it works. On four-hour bars, 48 of 240 settings took no trades at all in a year and 137 took fewer than ten. On hourly bars, 20 took none and 81 took fewer than ten. Most advice about MFI settings cannot be evaluated on forex's higher timeframes for lack of a sample.
- How is MFI different from RSI?
- MFI is RSI weighted by volume: it compares up bars and down bars with their volume included. Forex has no consolidated exchange volume, so what a chart shows is only what one data source observed. The weighting that gives MFI its name rests on weaker ground here than it does in equities.
- What win rate does MFI produce?
- Restricted to settings that took at least 20 trades, the long side on hourly bars in 2025 ran from 47.5% to 72.73%. The median net result was −304 pips and only 13 of those 65 settings finished positive — high win rates without the result, as with other counter-trend indicators.
- Is MFI built into MetaTrader?
- Yes. Both MT4 and MT5 ship it as Money Flow Index under Oscillators. TradingView lists it as "Money Flow Index". Formiq's charts include it with an adjustable period.
Formiq is a free browser-based FX terminal with replay practice and no-code backtesting. Open the chart or see what the free plan includes.