What Is RSI? A Beginner’s Guide to the Relative Strength Index
Learn what RSI is, how it works and why crypto futures traders use it to understand momentum.
What RSI measures
The Relative Strength Index compares recent upward and downward price changes. Its scale runs from 0 to 100. A high reading means recent gains dominate losses; it does not measure the probability of a profitable trade. The lookback and smoothing method matter when comparing two platforms.
A simple calculation
If average gains are 2 and average losses are 1, relative strength is 2. RSI = 100 − 100 / (1 + 2), or about 66.67. In this scanner, RSI uses a rolling sum of gains and losses over 14 changes on 15-minute closes. This differs from Wilder smoothing often used by charting platforms.
Read the scanner correctly
Compare the same symbol, candle interval, period and smoothing method. The latest candle may still be forming. The OB count counts candles with RSI at or above 70 in the last 96 readings; it is not a count of independent trade entries.
Reproduce a 14-change window
Hypothetical worked example. Seven gains of 2 and seven losses of 1 give total gains of 14 and losses of 7. The ratio is 2; RSI is 66.67. If the next close removes a +2 change and adds a −2 change, the sums become 12 and 9, and RSI becomes 57.14. The reading can move because an old change leaves the window as well as because a new change enters it.
Why can a chart show a different number?
Compare interval, current versus closed candle, price feed and smoothing method. FuturesRadar uses simple rolling sums, while many chart defaults use Wilder smoothing.
Verify the assumptions
Check the input window, fees and data availability before applying this example. For the exact software behavior and coverage limits, read the scanner methodology. Examples explain arithmetic and interpretation; they are not historical performance claims.