Key takeaways · 5
- Coil is a 0-100 tightness score, where 100 is the tightest. It measures how compressed a stock’s recent daily range is, so a high coil marks a name whose price swings have contracted to a narrow band.
- The raw ingredient is a 4-day average of true range divided by price, normalised range rather than raw dollars. Dividing by price is deliberate: it stops the score from reading a cheap, drifting-down stock as "tight."
- The score is the smaller of two legs. One is relative: how tight the current range is against the same stock’s prior 60 sessions. The other is absolute: a fixed map where 2% average range or less scores 100 and 8% or more scores 0. Taking the minimum means a name has to be tight both ways.
- The absolute leg is why the two-leg design exists. A pure "tight for this stock" percentile is scale-free: a wild name reads tight the moment it is merely calmer than its own chaos. The absolute floor forces a high coil to mean tight on the tape, not just tight for itself.
- In the terminal,
coilis the score.coil>90 | chartwalls the tightest names for a visual pass, which is how most people use it: the number narrows the field, the chart confirms the base.
Why tightness is worth measuring
Big moves tend to come out of quiet. A stock that has been swinging 6% a day rarely launches a clean breakout from that noise; the launches come after the swings contract and the chart goes quiet. Traders describe it as coiling, or a spring winding up. The tighter the range gets, the less room there is for the stock to keep doing nothing, and the more a decisive move resolves the tension one way or the other.
That makes tightness a useful thing to screen for, but it is hard to eyeball across thousands of names. A chart can look tight and not be, or be tight in a way that is normal for that particular stock. Coil exists to put one comparable number on it, so you can rank the whole universe by how wound-up each name is and then take the tight ones to the chart.
Coil does not predict direction. A tightly wound stock can break either way, and plenty of tight bases fail. What the score reports is a condition: stored energy, not a forecast of where it goes. It is a filter for where a move is more likely to be clean, not a signal that a move is coming.
Coil measures how far the recent daily range has contracted, then takes the smaller of a relative and an absolute reading so a high score means tight both ways.
The raw ingredient: normalised range
Everything in coil is built from one measurement: the true range of each day, divided by that day’s closing price, averaged over the last four sessions. True range is the standard measure of how much a stock moved in a day, including any overnight gap; dividing by the close turns it from dollars into a percent, and averaging four days smooths out a single wild session without blurring the recent picture.
The division by price does the real work here, and it fixes a specific failure. If coil used raw-dollar range, a $12 stock quietly bleeding lower would look "tight" next to a $400 stock, purely because twelve dollars cannot move as many dollars as four hundred can. Worse, a stock in a slow downtrend prints small daily ranges as it drifts, which a dollar-based measure would misread as a tightening base. Normalising by price puts every name on the same percentage footing and keeps the score honest about what tight actually means.
So the number under everything is simple: what percent of its price does this stock typically travel in a day, right now, over the last four sessions. A reading of 2% is a very quiet stock; 8% is a wild one. The rest of coil is about turning that percent into a comparable 0-100 score.
Two legs: tight for itself, and tight on the tape
Coil combines two readings of that normalised range and reports the smaller of the two. The design forces a high score to clear both bars rather than either one alone.
The first leg is relative. It ranks the current four-day range against the same stock’s prior 60 sessions, inverted so that tighter is higher: a stock at its narrowest range of the last three months scores near 100, one at its widest scores near 0. This is the intuitive read of "coiling": the stock has contracted relative to how it has been trading lately.
The second leg is absolute. It ignores the stock’s own history and maps the raw normalised range onto a fixed scale: 2% average daily range or tighter scores 100, 8% or wider scores 0, straight-line in between. This leg does not care whether the stock has calmed down relative to itself; it only asks whether the range is objectively narrow. Coil is the minimum of the two, so a name has to be both tight for itself and tight in absolute terms to score high.
Why the absolute leg exists
The two-leg design is a deliberate fix for a flaw in the relative leg alone, and it is worth understanding because it explains why coil is stricter than a plain "tightest range in 60 days" screen.
A time-series percentile is scale-free: it only knows a stock against its own past. Every name, no matter how wild, spends about one day in sixty as its own tightest, which means a stock with a habitual 6% daily range will score above 90 on the relative leg the moment it dips to a merely-calmer 5%. That is not a coiled base. It is a chaotic stock having a slightly quieter week, and a relative-only score would wave it through onto every tight-base list.
The absolute leg closes that door. By capping the score at whatever the fixed 2%-to-8% map allows, it forces the number down for any name whose range is still wide in absolute terms, no matter how calm it looks relative to its own history. A high coil now means two things at once: the stock has contracted, and it has contracted to a genuinely narrow band. That is the difference between "quiet for this stock" and "tight on the tape," and it is the whole reason the metric takes a minimum rather than an average.
Coil, ADR, and VCP
Three range ideas sit near each other, and they are not the same tool. Average Daily Range (ADR) is a level: the stock’s typical daily percent move, a filter for whether a name is lively enough to trade at all. Coil is a contraction score: how tight the range is right now, relative and absolute, a filter for whether a lively name has quieted into a base.
The Volatility Contraction Pattern (VCP) is the pattern coil is a proxy for. VCP is Mark Minervini’s name for a base that tightens in stages, each pullback shallower than the last, on falling volume. That is a shape read across a whole base by eye. Coil is the single-number, screenable version of the tail end of that story: it cannot see the sequence of contractions the way a chart can, but it can rank the universe by how tight things have become and surface the candidates a VCP eye would want to check.
The practical division of labour: ADR decides whether a stock moves enough to bother with, coil decides whether it has coiled, and the chart decides whether the contraction is the clean, staged kind worth acting on. Coil is the fast filter in the middle, not the final word.
Where coil misleads
Coil needs history. It reads the current range against the prior 60 sessions and requires roughly a full quarter of bars to compute, so a tight new issue returns no coil until it has traded long enough to fill the window. A blank coil on a recent listing means "not enough history," not "not tight."
Tight is not the same as ready, and coil says nothing about direction. A stock can wind to a very high coil and then break down instead of up, or grind sideways for weeks longer. The score marks stored energy; it does not mark the release or its sign. That is what the base under it and the trend it sits in are for.
And a high coil on its own is context-free. A tight range inside a healthy Stage 2 uptrend is a very different setup from an equally tight range in a broken downtrend, even though the coil number can be identical. Coil is a measurement of one property in isolation, which is exactly why it is meant to be paired with a trend read and a chart rather than traded off the number alone.
How tickerstance uses it
In the terminal, coil is the 0-100 score, computed for every name with enough history and shown in the score column so you can rank and filter on it directly. coil>90 returns the tightest names in the universe; coil>90 | chart walls them for a visual pass, which is the common workflow: the number narrows thousands of names to a handful, and the chart confirms which of those handful are real bases.
Coil composes with everything else. dt coil>85 finds Double Trouble names that have also tightened; stocks semis coil>90 finds the tightest names in a single industry; a saved leaders list piped through coil>90 surfaces the coiled leaders. Several of the named setups lean on coil internally as one of their gates, because "has it contracted" is a question almost every base-and-breakout setup needs answered.
Coil never feeds Stance either; it is a single-name measurement of tightness, and it settles only half the question. A high coil says a stock has wound tight. Whether that tension is worth anything depends on the base under it and the trend it sits in, which is what the chart is for.
Frequently asked questions
What is the coil metric?
A 0-100 score of how tight a stock’s recent daily range is, where 100 is the tightest. It is built from a 4-day average of true range divided by price, then combined into a single number that is high only when the stock has contracted to a narrow band. A high coil marks a name that has quieted into a potential base.
How is coil calculated?
It starts from the 4-day average of true range divided by the closing price (normalised range). Then it takes the smaller of two legs: a relative leg that ranks the current range against the stock’s prior 60 sessions (tighter scores higher), and an absolute leg that maps the normalised range onto a fixed scale where 2% or tighter scores 100 and 8% or wider scores 0. Coil is the minimum of the two.
Why does coil use both a relative and an absolute leg?
Because a relative-only score is scale-free and would be fooled by wild stocks. Every name spends about one day in sixty as its own tightest, so a stock with a habitual 6% range scores high the moment it dips to 5%, calmer for itself, but not a tight base. The absolute leg caps the score for any name whose range is still wide in absolute terms, so a high coil means tight both ways.
What is the difference between coil and ADR?
Average Daily Range (ADR) is a level: how much a stock typically moves in a day, used to decide if it is lively enough to trade. Coil is a contraction score: how tight the range is right now, relative and absolute, used to decide if a lively stock has quieted into a base. ADR asks "does it move enough"; coil asks "has it coiled."
Is coil the same as a VCP?
No. Coil is a single-number proxy for the tail end of a VCP. The Volatility Contraction Pattern is Minervini’s multi-stage base where each pullback is shallower than the last on falling volume, read across a whole base by eye. Coil cannot see that sequence; it measures how tight things have become right now and surfaces candidates a VCP eye would want to check on the chart.
Does a high coil mean a stock is about to break out?
No. Coil measures stored energy, not its release, and it says nothing about direction: a tightly coiled stock can break down, or stay quiet for weeks. It is a filter for where a move is more likely to be clean, not a signal that a move is coming. Pair it with the trend and the base under it before reading anything into the number.
How do I screen for coiled stocks on tickerstance?
Type coil>90 in the terminal for the tightest names, and coil>90 | chart to wall them for a visual pass. Combine it with anything else: dt coil>85 for tightened Double Trouble names, or stocks semis coil>90 for the tightest names in an industry. Several named setups also use coil internally as one of their gates.