Riegel Formula: T2 = T1 × (D2/D1)^1.06. Developed by Pete Riegel (1977). Accurate within ~2% for most runners.
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Sources & Further Reading
Reviewed May 29, 2026. Tool outputs are estimates for gear fit, training, or shopping context. Confirm league rules, personal fit, and safety-sensitive decisions with qualified coaches, fitters, clinicians, or local avalanche professionals where relevant.
This calculator is a starting point. Use the result alongside current TSP guides, returnable purchase paths, and deal tracking instead of retailer searches.