Bollinger Bands Calculator
Calculate rolling lower, middle and upper Bollinger-style bands from ordered prices you enter, using a simple moving average and an explicit N-divisor population deviation. The page reports band width and latest-price location but does not fetch candles, classify band touches or predict reversals, breakouts or future volatility.
Enter ordered prices
Use one consistent symbol, timeframe, broker feed and applied-price basis.
One row per line: price alone, or optional label then price. Commas, semicolons or tabs are accepted.
Current entered-price envelope
Entered Price Statistics 1.0.0.
| Label | Entered price | Lower | Middle | Upper |
|---|
How the Bollinger bands are calculated
Population deviation = √[Σ(price − middle)² ÷ N]
Upper / Lower = Middle ± multiplier × deviation
The rolling middle band is a simple moving average. The deviation follows the MetaQuotes published Standard Deviation indicator convention and divides the squared-deviation total by N.
Latest-price location is measured across the lower-to-upper span. It remains unclassified, and values below 0% or above 100% are retained rather than converted into a trading label.
Worked example from the audited fixture
How to interpret the result
The latest price is inside this entered-window envelope and above its middle, but that location does not establish overbought conditions, a breakout or a reversal. A chart can differ because of applied price, shift, averaging method, deviation divisor, history length or rounding conventions.
Assumptions and limits
- All observations must use one symbol, timeframe, broker feed and applied-price basis.
- Labels are descriptive; the tool does not sort rows or infer missing candles.
- A zero-deviation window collapses both bands onto the middle and makes within-band location undefined.
- Different platforms or custom indicators can use different averaging, deviation or seeding conventions.
- Bands do not predict reversals, breakouts, targets or future volatility.
Frequently asked questions
- It uses only the ordered positive prices entered in the browser and does not fetch chart candles.
- The middle band is the simple moving average of the latest N entered prices.
- Version 1.0.0 divides the sum of squared price deviations by N and takes the square root.
- The entered multiplier times population deviation is added to and subtracted from the middle band.
- Deviation and band width are zero, so all bands coincide and within-band location is undefined.
- It means the latest entered price is arithmetically above the current upper band; the page does not label it a breakout.
- No. The page reports an entered-price envelope without a reversal, trend or market-state classification.
- Not necessarily. Applied price, history, averaging and deviation conventions can differ across platforms and custom indicators.
Sources and methodology
- MQL5 Reference — iBands — Official period, shift, deviation and applied-price interface.
- MetaQuotes Code Base — Standard Deviation — Published N-divisor deviation formula and Bollinger-band relationship.
- MQL5 Reference — iMA — Official moving-average interface used for the middle-band context.
Continue range and volatility analysis
Compare the chart feed and trading terms
Use one consistent broker feed for every entered observation and verify the symbol's price precision, spread and trading conditions before using any measurement in a plan.
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