The Mountaineering Truth Project · Investigation 05

The AMS Risk Calculator

Estimate your personal Acute Mountain Sickness, HACE, and HAPE risk for your next high-altitude trip. Built on the 2018 Lake Louise Score, Wilderness Medical Society guidelines, and peer-reviewed altitude medicine literature. This is a planning aid, not medical advice.

Important — read before using This calculator estimates relative risk based on published prevalence data and known risk factors. It is not a medical diagnosis or substitute for professional medical advice. Individual susceptibility to altitude illness varies and cannot be fully predicted. Always consult a physician familiar with travel medicine before any high-altitude trip — especially if you have any pre-existing condition. If you develop symptoms at altitude, follow the gold-rule of altitude medicine: do not ascend further with symptoms; descend if symptoms worsen.

Your trip and risk profile

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Altitude profile

e.g. Kilimanjaro = 5,895 · Everest BC = 5,364 · Aconcagua = 6,961 · Everest summit = 8,849
Often lower than max altitude. Sleeping altitude is the primary risk driver — not summit altitude.
Above 3,000m, sleeping elevation should rise no more than ~500m/day. Faster = more risk.
Living at higher elevation provides modest baseline protection.

Individual factors

Younger climbers have slightly higher AMS risk; over-65 may have other altitude-related cardiac risks.
Recent altitude exposure provides meaningful protection — the strongest predictor we know.
Fitness has a smaller effect than people think. Acclimatization is largely independent of fitness.

Risk modifiers (check all that apply)

Sources & methodology. Risk estimates are derived from peer-reviewed altitude medicine literature: Roach et al. (2018) — The 2018 Lake Louise Acute Mountain Sickness Score; Hackett & Roach — High-Altitude Illnesses; StatPearls/NCBI — Acute Mountain Sickness clinical reference; CDC Yellow Book 2024 — High Elevation Travel & Altitude Illness; Wilderness Medical Society guidelines. Baseline AMS prevalence figures use the published 13% per 1,000m increase above 2,500m benchmark. Risk-modifier multipliers reflect documented relative-risk values (prior AMS history ~2x; pre-acclimatization protective; ascent rate primary modifier). The model is a transparent points-based estimator — not a clinical tool. Always consult a physician before high-altitude travel. If you develop symptoms at altitude: do not ascend further with symptoms, descend if symptoms worsen, and treat severe symptoms as life-threatening emergencies. Contact the editorial team.