# MFI (Money Flow Index)

> The Money Flow Index is a volume-weighted version of RSI: an oscillator scaled 0 to 100 that compares money flowing in on up sessions to money flowing out on down ones over 14 bars.

Canonical: https://patternsradar.com/learn/mfi

MFI starts where RSI does but weighs each session by the money that traded in it: the typical price times volume. Sessions where the typical price rose count as inflow, sessions where it fell count as outflow, and the ratio over 14 bars is scaled 0 to 100. A quiet drift higher barely moves it; the same price path on heavy volume drives it hard. It is momentum measured in rupees rather than in sessions.

The conventional levels are 80 and 20 — slightly wider than RSI's, because the volume weighting makes MFI jumpier. The reading traders care most about is disagreement: price grinding higher while MFI slides means the advance is happening on shrinking money flow, which is how distribution looks from the outside. On NSE dailies it pairs naturally with delivery percentage — MFI infers conviction from volume, delivery reports it — and agreement between the two is worth more than either alone.

The volume weighting is also the vulnerability. One block deal or rebalancing day can dominate the 14-bar window and pin MFI at an extreme that reflects a single transaction, not a campaign — in thin smallcaps this happens routinely. And like every oscillator, its extremes are descriptions rather than limits: under 20 in a genuine downtrend means heavy selling is happening, not that it is finished.

Against RSI the difference is exactly the volume term: RSI would score a 1% rise on ten times average volume and a 1% drift identically, while MFI scores the first ten times harder. When the two disagree, volume is the reason — and which one was right about that stock is a question the replay can answer.

## In Sift

Written as `mfi(14)`. A working scan — stocks with money flow washed out below 20 while still above the 200-day average:

```sift
where mfi(14) < 20 and close > sma(200)
```

1 of the 500 most-traded NSE stocks match today, as of 2026-08-20.

## Scans that use it

- [Money flow oversold](https://patternsradar.com/screener/mfi-oversold.md): Money Flow Index under 20 — RSI's volume-weighted cousin, at an extreme.

## Common questions

### What is the difference between MFI and RSI?

MFI is RSI with each session weighted by the money that traded in it — typical price times volume — instead of counting all sessions equally. A move on heavy volume drives MFI far harder than the same move on light volume. The two diverging on the same chart means volume is favouring one side, which is the reading traders look for.

### What does MFI below 20 indicate?

That over the last fourteen sessions, money flow on down days has overwhelmed money flow on up days to an unusual degree. In a stock whose long-term trend is intact, traders read it as selling running out of participants; in a downtrend it simply describes the decline. The trend filter, not the number, decides which reading applies.