Frequently Asked Questions

Marginally, on the standard test pad with base layers - and only if every real-world factor cooperates. A worse pad costs about 3 °C per R-point below 5, damp insulation or wind costs more, and cold sleepers should subtract another 3 °C. The warmth calculator exists exactly because the label number assumes conditions you will not have.

Comfort (ISO standard woman) for planning, lower limit (standard man) as a survival number. The sleeping bag temperature calculator outputs both requirements for your trip so you can shop against the honest one.

The model credits 3 °C per clo up to 3 clo - base layers, a light puffy and a beanie together are worth roughly 4-6 °C. Beyond that, bulk compresses the bag and the credit stops being real.

Against the back panel, between shoulder-blade height and the middle of the pack - high on easy trails, lower for steep or scrambling terrain. The backpack balance calculator checks your actual zone weights against that target.

A common ceiling is 20% of body weight for maintained trails. Placement matters as much as the total: a well-balanced heavier pack carries better than a badly balanced lighter one.

Yes, everything lives in your browser (localStorage) and never leaves it. The print button produces a clean paper list with the site chrome removed.

The Pandolf equation for a 70 kg hiker with a 12 kg pack covering 20 km of rolling trail lands around 3,500-4,500 kcal including a modest base overhead. The hiking calorie calculator returns the number for your specific day; the food calculator converts it to grams.

Between 0.3 and 1.5 L per hour depending on effort, heat and humidity - most moderate days near 20 °C work out to about 0.5-0.7 L/h. The hiking water calculator gives the rate and total, plus when to plan refills instead of carrying.

Grocery-food menus sit near 330 kcal/100 g, standard mixed menus near 450, nut-and-oil-heavy ultralight menus near 550. The backpacking food calculator has presets for all of them.

About 6.5 °C per 1,000 m on average. Valleys can invert on clear nights. The altitude temperature calculator applies the standard rate in either direction and unit.

Above 3,000 m, no more than 500 m of sleeping-altitude gain per day with a rest day every 1,000 m - the Wilderness Medical Society consensus the altitude sickness risk calculator scores against.

Water boils near 90 °C there instead of 100 °C, and cooking chemistry roughly halves per 10 °C drop. The boiling point calculator shows the exact temperature and pressure; the altitude cooking guide covers fuel planning.

Factor 2 - falling twice the rope length in play, only possible from at or below the anchor with slack - is the worst case a rope system can see and approaches gear limits. Factor 1 is already a serious fall. The fall factor calculator estimates the forces, with honest notes on what it ignores.

Above 120°. Each leg carries half the load only at 0°, 58% at 60°, 71% at 90°, the full load at 120°, and nearly double above 150°. The anchor force calculator shows the multiplier table live.

They are physics references, not rigging instructions. Real anchors involve friction, unequal legs and dynamic loads the models ignore. Learn anchoring from qualified instruction; use these tools to understand why the rules exist.

No. Every tool runs entirely in your browser; inputs persist only in localStorage under oc.* keys. The privacy page details exactly what is and is not collected.

Published, citable sources: the Pandolf load-carriage equation, EN 13537 / ISO 23537 rating methodology, NWS wind chill, the Clausius-Clapeyron relation and standard vector statics. Each tool page states its basis and its assumptions.