What this tool does
The Fibonacci Retracement Calculator takes a swing high and a swing low from your chart and plots the classic Fibonacci levels — 23.6%, 38.2%, 50%, 61.8% and 78.6% — between them. These levels come from ratios found in the Fibonacci number sequence and are widely watched by traders as potential areas where price might pause, bounce, or reverse during a pullback.
The tool can also project extension levels (100%, 161.8%, 261.8%) beyond the original swing, which traders use to estimate where a trend might run out of steam. These levels are not magic lines — they work partly because so many traders watch them that they become self-fulfilling. Always combine them with price action, trendlines, or other confirmation rather than trading a Fib level on its own.
How to use it
- Identify a clear swing high and swing low on your chart (a completed price leg).
- Enter the high price and the low price into the calculator.
- Choose whether the move was uptrend (low to high) or downtrend (high to low).
- The calculator draws the retracement levels between the two points.
- Mark the 38.2%, 50% and 61.8% levels on your chart — these get the most attention.
- Watch how price reacts at each level; a bounce with confirming price action is stronger than the level alone.