Testing & Methodology
Last updated: November 8, 2026
What “tested” means on HWTUTU
If a page says a product, route or technique was tested, that means first-hand use by the author or a named contributor. The page should state the duration, the conditions and what was measured. We do not use “tested” to mean “read the specification sheet” or “asked an AI model”.
Most guides are research-based. They are compiled from public sources, official guidance, published formulas and manufacturer documentation, then edited for clarity and consistency. That is useful for planning, but it is not the same as independent lab testing. If a page does not contain a testing statement, assume it is research-based.
How the calculators work
Each tool states its method on the page. The table below summarises the main formulas and the most important limitations.
| Tool | Method | Main limitation |
|---|---|---|
| Hiking Time | Naismith’s rule: walking time at the chosen pace plus one hour per 600 m of ascent, adjusted for terrain, pack weight and breaks. | Weather, altitude, navigation errors, group pace and trail conditions can add a lot of time. It is a planning baseline, not a schedule. |
| BMI | Weight in kilograms divided by height in metres squared. | Does not distinguish muscle from fat; not designed for children, pregnant people or highly muscular athletes. |
| Waist-to-height ratio | Waist circumference divided by height, using the same unit. | Measurement placement matters. It is a screening signal, not a diagnosis. |
| Body Fat | US Navy circumference method (neck, waist and hip for women). | Sensitive to tape placement and body shape; population-specific and less accurate than DEXA or hydrostatic weighing. |
| Water Intake | About 35 ml per kg of body weight, plus roughly 600 ml per hour of exercise, plus a climate adjustment. | Sweat rate varies widely. Medical conditions, medication and very long efforts need individual advice. |
| Calorie Needs | Mifflin-St Jeor BMR, an activity multiplier for daily maintenance, and a 6 MET hiking estimate minus resting metabolism. | An estimate with wide individual variation; food labels and wearable devices have their own error margins. |
| Heart Rate Zones | Tanaka estimated maximum heart rate (208 − 0.7 × age), with optional Karvonen zones using resting heart rate. | A formula estimate, not a lab test. Medication, heat and fatigue change heart rate. |
| Pack Weight | Sum of the gear weights you enter, split into base weight and consumables. | Depends on your scale and what you remember to include; worn weight is not counted. |
| Sleeping Bag Decoder | Explains EN 13537 / ISO 23537 comfort, limit and extreme ratings against a planned night temperature. | Pad R-value, clothing, metabolism, tent conditions and hydration change the real-world result. Comfort is the rating to plan with. |
| Camping Checklist | Rule-based list generated from trip type, season and duration, with optional items you can add or remove. | Not destination-specific. Check local regulations, weather and permit requirements before you go. |
| Morse Code | International Morse alphabet with standard dot, dash and gap timing. | Timing and audio are for practice; real signalling requires a reliable light, whistle or radio and a clear protocol. |
What the calculators cannot do
- They cannot see your fitness, health history, load, terrain or the weather.
- They cannot replace a map, compass, route plan or local advice.
- They cannot guarantee that a result is safe for your specific trip.
- They are not medical devices and do not diagnose or treat any condition.
Gear and product information
Product specifications come from manufacturer documentation and retailer listings. We do not run a lab, and we do not claim to have tested every item mentioned on the site. Prices, models and availability change constantly; check the current specification sheet and safety notices before buying or using gear.
HWTUTU does not currently use affiliate links. If that changes, the relationship will be disclosed in the Affiliate Disclosure and on the page where the link appears; it will not change the price you pay or the editorial conclusions.
Trails, parks and conditions
Route and destination pages use official land-agency or park guidance where it is available. Conditions change faster than any website: closures, permits, fires, floods, snow and wildlife rules can change overnight. Confirm the current rules with the managing agency before you travel, and carry a map and a way to communicate.
Health and fitness content
BMI, body-fat, hydration, calorie and heart-rate tools are educational screens. They are built from published formulas and checked for numerical consistency, but they are not a substitute for individual medical advice. See the Safety & Medical Disclaimer.
How we update and retire content
Pages are reviewed when a standard, formula, regulation or product specification changes, or when a reader reports an error. Safety-critical corrections are prioritised. If a page can no longer be maintained accurately, we revise it or remove it rather than leave stale advice online. The date at the top of each page shows the latest substantive update.
Report an error
Email liuxihope@gmail.com with the page URL, what you believe is wrong and, if possible, a source that supports the correction. See also the Editorial Policy and Content Sources & Accuracy.