True strength index
A momentum oscillator built from two layers of EMA smoothing applied to price changes, aiming to filter noise while still reacting reasonably quickly.
What the numbers mean
Twenty-five is the first EMA period applied to daily price changes, 13 the second EMA applied to that result, and 7 the signal-line EMA. Double smoothing is what separates TSI from raw momentum: it keeps the sign and general shape while removing most of the jitter.
- 25 — the first EMA applied to daily price changes
- 13 — the second EMA applied to that result
- 7 — the signal-line EMA
- 0 — the trend dividing line; double smoothing keeps it unusually clean
How it is used
Read for zero-line crossings as the trend indication, signal-line crossings as the entry, and divergence — which is unusually legible on TSI because the line is so smooth.
- Zero-line crossings → trend direction
- Signal-line crossings → entry timing within that trend
- Divergence → unusually legible, because the line is so smooth
How it relates to everything else
TSI is momentum with two layers of EMA applied, which puts it between MACD and TRIX on the smoothness ladder. Its clean line is what makes it a favourite for spotting divergence, where MACD's jitter can create patterns that are not really there.
- Smoother than MACD, faster than TRIX
- Divergence is its strongest use, more than its crossings
- Unbounded, so extremes must be judged against the security's own history
What to watch for
Two layers of smoothing means real delay at turns, and the scale is unbounded, so extremes have to be judged against the security's own past readings.