📊 TECHNICAL
Force Index
Combines price change and volume into a single momentum reading, showing whether a move has real conviction behind it or is running on empty.
195KUses
17800Likes
0Comments
Live Demo — Force Index applied to NIFTY 50 (illustrative)
PriceEMA(9)EMA(21)SMA(20)
What is the Force Index?
Introduced by Dr. Alexander Elder, it multiplies the change in price by the volume that accompanied it, capturing both direction and conviction of a bar's move. Elder recommended smoothing it with a short EMA.
Formula
Force Index(raw) = Volume(t) * (Close(t)-Close(t-1))
Force Index = EMA(n, Force Index(raw))Parameters
| Parameter | Default | Description |
|---|---|---|
| EMA length | 13 | Smoothing period; a 2-period variant is used for shorter-term signals |
Signal Interpretation
- A strong positive spike shows a price rise backed by heavy volume — real buying conviction.
- A strong negative spike shows a drop backed by heavy volume — real selling conviction.
- A weak/fading reading during a price move suggests the move lacks volume support.
- Zero-line crosses on the 13-period version can mark shifts in the underlying trend's force.
- Divergence between price and Force Index can precede reversals.
Tips & Best Practices
- Use the short EMA version to time entries within an established trend, and the longer version to judge overall trend strength.
- Spikes can be dominated by unusually high-volume news bars — read them in context.
- Combine with price trend analysis; Force Index confirms conviction but doesn't define levels.