How it works
Ichimoku is a complete system rather than an indicator, and its components share one idea: equilibrium is the midpoint between the highest high and the lowest low of a lookback, not an average of closes. That choice matters. A midpoint of extremes is unaffected by how price travelled inside the range, so the lines are flat when the market is range-bound and step decisively when a new extreme is made — a very different signature from a moving average, which drifts continuously.
Five lines do the work. The conversion line is the 9-period midpoint, the fast equilibrium. The base line is the 26-period midpoint, the slower one that acts as the system’s main reference level. Two more lines are pushed 26 periods into the future: leading span A, the average of the two equilibrium lines, and leading span B, the 52-period midpoint. The area between those two spans is the cloud. Finally the lagging span plots the current close 26 periods into the past, which compares today’s price directly against the market of a month ago.
The projection is what makes the chart look unusual and what makes it useful. Because the spans are drawn forward, the cloud shows support and resistance before price arrives there, derived entirely from prices that have already happened. A thick cloud comes from a wide gap between the two equilibrium measures and marks a zone the market spent time and range building; it tends to absorb pullbacks. A thin cloud, or a twist where the spans cross, marks a fragile zone that price cuts through easily.
A conventional bullish reading requires several things to agree: price above the cloud, the conversion line above the base line, the cloud ahead of price bullish in colour, and the lagging span above the price action of 26 bars ago. The requirement that everything agrees is the system’s real contribution — it is a checklist that keeps a trader out of ambiguous conditions, and it is why Ichimoku signals are relatively rare and relatively late.
Against its neighbours: Ichimoku answers the same broad question as a moving-average ribbon but adds forward-projected levels and an explicit past comparison. It is not a momentum tool and it is not a volatility tool. Where Donchian channels take the same extremes and draw a breakout box, Ichimoku takes their midpoints and builds an equilibrium map.
Calculation
The arithmetic in words, in the order it happens.
The conversion line is the average of the highest high and the lowest low over the last 9 periods. The base line is the same midpoint over 26 periods. Leading span A is the average of the conversion and base lines, plotted 26 periods ahead. Leading span B is the midpoint of the highest high and lowest low over 52 periods, also plotted 26 periods ahead; the shaded area between the two spans is the cloud. The lagging span is simply the current close plotted 26 periods back. Every line uses midpoints of extremes, never averages of closes.
Source
An AlgoBeamScript implementation of the formula above, written by us from the arithmetic so the code and the calculation agree line for line.
Runs unchanged on the platform and in the AlgoBeamTS runtime. The language reference is in the documentation.
Inputs
Defaults are the values most charting packages ship with. They are conventions, not optimal settings — the right length depends on your instrument and your holding period.
| Input | Default | What it changes |
|---|---|---|
| Conversion line periods | 9 | Lookback for the fast equilibrium. Shorter values make it hug price and produce more conversion-base crossovers; the default represents roughly a week and a half of daily sessions. |
| Base line periods | 26 | Lookback for the main reference line and, in practice, the system’s trend anchor. It also drives the natural stop level for many Ichimoku traders, so lengthening it widens risk on every trade. |
| Leading span B periods | 52 | Lookback for the slow edge of the cloud. Larger values give a thicker, more stable cloud with longer flat stretches; those flat sections often act as strong reference levels precisely because no new extreme has occurred. |
| Displacement | 26 | How far the cloud is projected forward and the lagging span pushed back. It is conventionally the same as the base line period; changing it alters both the forward levels and the historical comparison at once. |
How to read it
What practitioners take from the plot. Read these as descriptions of market state, not as entry signals.
- Price above the cloud
- Bullish regime by the system’s definition. The cloud below then acts as the first zone where a pullback is expected to find support.
- Price inside the cloud
- No trend. Equilibrium is unresolved and the system considers the market untradeable; most Ichimoku rules simply stand aside here.
- Conversion line crossing above the base line
- A momentum trigger. Its weight depends entirely on where it happens: above the cloud it is a continuation signal, inside or below it is noise.
- Cloud twisting, spans crossing ahead of price
- A projected inflection. The zone where the two spans swap places is thin by construction and is where price most often passes through the cloud cleanly.
- Lagging span above the price bars of 26 periods ago
- Today’s price is better than the market of a month ago in open space. The confirmation most Ichimoku traders wait for, and the one that makes signals late.
Limitations
Where this indicator misleads. None of these are fixed by a better parameter.
- It needs a lot of chart. Five lines, a shaded band and a displaced series is dense, and beginners routinely read a bullish component in isolation while three others disagree.
- The whole system lags, deliberately. Requiring price, cloud, crossover and lagging span to agree means the entry arrives well into the move, and the base-line stop is often far away by then.
- It is built for trending markets. Inside the cloud the lines flatten, crossovers repeat and every signal fails — which the system handles by refusing to trade, but that means long idle periods.
- The default 9, 26 and 52 come from a market week that no longer exists, since Japanese exchanges traded Saturdays when the periods were chosen. They survive by convention and self-fulfilment, not because those specific lookbacks are optimal.
Educational reference. This page explains how an indicator is built and how it is commonly read. It is not investment advice, not a recommendation and not a signal service. No indicator is profitable on its own — each is a way of describing a market, and any rule built on one has to be tested with realistic costs before it is traded.