Price Envelopes Indicator: Formula, Settings and How to Read It
Price Envelopes draw two lines a fixed percentage above and below a simple moving average of the close. Senzoukria uses a 20-period basis and a 2.5 percent deviation by default, so the width of the band follows the price level and not the volatility.
Senzoukria · Indicators · Updated September 2026
Price Envelopes ships with the Senzoukria desktop app, in the Averages & volatility group of the indicator catalogue. It is drawn on the price chart.
What Price Envelopes measures
The basis is an ordinary simple moving average; the upper line is that basis multiplied by 1 plus the percentage, the lower by 1 minus it. Band width is therefore proportional to the price level: at a basis of 4,000 index points, a 2.5 percent setting places each line 100 points away, and that distance changes only as the basis does. This is what separates the envelope from the other band families in the catalog, where width comes from a standard deviation or from ATR. All three lines begin on the same bar, since the two outer ones are derived from the basis.
The formula, as implemented
This is not a description of how the indicator is usually defined elsewhere — it is what the shipped code computes, documented next to the implementation:
Price Envelopes : basis = SMA_N(close) ; upper = basis·(1 + p/100) ; lower = basis·(1 − p/100) Enveloppe en POURCENTAGE du basis (pas en σ ni en ATR — c'est ce qui la distingue de Bollinger/Keltner déjà livrés). Warm-up SMA → null. Défauts N=20, p=2.5 %.
How to read it
- Read a touch of the upper or lower line as price being a fixed percentage away from its 20-bar mean, which is a statement about distance, not about a reversal.
- If price rides one line for many bars, the chosen percentage is narrower than the instrument's current range; widen it before drawing conclusions from the touches.
- The band does not widen when volatility rises, so the number of touches over a session changes with conditions while the setting stays where you left it.
- The envelope is centred on a simple average, so the midline carries that average's lag and both outer lines inherit it.
Parameters and defaults
Period defaults to 20 in a 1 to 500 range and drives the basis alone; deviation defaults to 2.5 percent and accepts 0.1 to 25. The right percentage differs by instrument and by timeframe: a value suited to an index future on a one-minute chart is far too narrow on a daily chart of the same contract, because the setting is fixed and never adapts.
| Parameter | Type | Default | Range |
|---|---|---|---|
| Period | number | 20 | 1 – 500 |
| Deviation % | number | 2.5 | 0.1 – 25 |
What it does not show
A percentage envelope carries no information about volatility. It keeps the same relative width through a quiet session and through a violent one, so touches mean very different things in each. The percentage is relative to the basis, which means the absolute distance changes when the price level changes even if nothing else does. And a touch says nothing about whether resting liquidity absorbed the move or aggressive orders drove it; that reading comes from the footprint cells or the liquidity heatmap, not from the envelope.
Using it in Senzoukria
Add it from the Indicators panel of any footprint chart or candle chart. It runs on futures data from Rithmic or Databento and on crypto pairs from Binance and Bybit, on the same engine — the calculation does not change with the venue, only the data feeding it does. Market data subscriptions are billed by the provider, separately from the app.
Related indicators
- SMA — Averages & volatility
- EMA — Averages & volatility
- WMA — Averages & volatility
- Hull MA — Averages & volatility
- ATR (Wilder) — Averages & volatility
- Bollinger — Averages & volatility
See the full indicator library, or start with the order flow guide if you are new to reading aggression, delta and absorption.
Frequently asked questions
- What is the difference between price envelopes and Bollinger Bands?
- Both are centred on a moving average, but the width is computed differently. Price Envelopes use a fixed percentage of the basis, 2.5 percent by default here, so the band keeps the same relative width whatever the market does. Bollinger Bands use a standard deviation of price, so they expand when volatility rises and contract when it falls.
- What deviation percentage should I use for price envelopes?
- There is no universal value, because the setting has to match the typical range of the instrument and the timeframe you are looking at. A practical approach is to adjust the percentage until the lines sit just outside most of the recent bars, then leave it fixed so that touches stay comparable over time. The default is 2.5 percent and the allowed range is 0.1 to 25.
- Do price envelopes widen when volatility increases?
- No. The width is a fixed percentage of the moving average, so it changes only when the average itself changes level. For a band that responds to volatility, use a standard-deviation band or an ATR-based channel instead; the envelope is the non-adaptive member of the family by design.