How the Range Filter indicator works
One open indicator sits behind every signal. Here is its logic step by step — no formulas, but nothing hidden either.
Where it comes from
Range Filter is a well-known TradingView indicator; the original was written by DonovanWall, and variants tuned for lower timeframes followed. TradeRadar uses the same logic, rewritten as server-side code and computed on Binance candles.
Our parameters: a sampling period of 20 bars and a range multiplier of 3.5. Popular TradingView versions default to 50 and 3.0, so our variant reacts noticeably faster.
Step 1. Measure the usual range
We take the absolute change in closing price from candle to candle and smooth it twice with an exponential moving average. The result answers the question "how much does this instrument typically move per bar right now". Multiplied by the range multiplier, it becomes the half-width of the channel.
The point is that the channel adapts by itself. It is narrow on a quiet pair and wide on a volatile one, so the same indicator works on both without manual tuning.
Step 2. Move the line in steps
The filter line is not a moving average. It stands still while price stays inside the channel and shifts only when price breaks out of it. Hence its characteristic stepped shape.
This is what removes the noise: small swings inside the channel never touch the line, and false reversals are less frequent than with ordinary averages.
Step 3. Catch the reversal
Direction is decided simply: the line is either higher than on the previous bar or lower. The buy condition is price above the line, direction up, price changed. The sell condition is the mirror image.
But a signal is not placed on every bar that satisfies the condition — only on the first bar of a new wave, where the previous state was the opposite one. That is why a long trend shows one flag, not a hundred.
Strengths and weaknesses
- Strength: on pronounced trends it enters early and holds direction until a real reversal.
- Weakness: in a tight range the channel contracts and reversals multiply. That is inherent to the approach, not a malfunction.
- It lags by definition: it is computed on closed candles and does not predict the future.
- Identical parameters for every pair are a compromise. For a specific instrument they could be tuned more precisely.