Fibonacci Retracement and Extension Calculator

This Fibonacci calculator derives the 23.6%, 38.2%, 50%, 61.8% and 78.6% retracement levels plus the 127.2%, 161.8% and 200% extension levels from your swing high and low.

Use the output as a map of potential reaction zones, then compare it with market structure and price confirmation. A Fibonacci ratio does not predict that price must reverse.

Fibonacci Calculator

Retracement and extension from one price swing

Results use only the values you enter; this is not a live market-data feed.

How to use the Fibonacci calculator

Enter the high and low of one clearly defined price swing, choose the swing direction, and calculate. Use the same data feed and timeframe throughout the analysis.

  1. Select a completed or clearly defined impulse swing.
  2. Enter its high and low, then choose uptrend or downtrend.
  3. Compare the levels with swing points, support/resistance and price confirmation.
  4. Define invalidation and position size before taking risk.

Formula used

For an upswing, retracement = High − (High − Low) × ratio. Extension = Low + (High − Low) × extension ratio. The calculation is reversed for a downswing.

Worked example

Hypothetical example: a rise from 100 to 120 has a range of 20. The 61.8% retracement is 107.64, while the 161.8% extension is 132.36.

How to interpret the result

Treat each number as an area to investigate rather than an automatic entry. A level becomes more useful when it aligns with structure, supply and demand, a trendline or a tested setup rule.

Limitations and common mistakes

  • Using arbitrary swing points.
  • Assuming every ratio must hold.
  • Treating an extension as a guaranteed target.
  • Ignoring execution costs and invalidation.

Recommended learning resources

Frequently asked questions

Which Fibonacci retracement level is best?

No single ratio works in every market. Traders commonly monitor 38.2%, 50% and 61.8%, but context and confirmation matter more than the number alone.

Can this calculator be used for forex, gold and crypto?

Yes, as a proportional measuring tool, provided the swing high and low are selected consistently.

Risk notice: This calculator is an educational planning aid, not investment advice or a trading signal. Trading can result in loss of capital. Input quality, spreads, slippage and changing volatility can make live results differ from estimates.

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