Free gear calculators that give you a usable answer
Size a weighted vest, plan water and pack volume, check carry-on gear, estimate sleeping-bag warmth, and build a safer trip. Free to use and free to embed.
Camp power, figured out
Size a station, estimate CPAP and fridge runtime, plan a solar refill, and check whether a panel is electrically compatible.
Fitness
4 tools
Weighted-Vest Sizing Calculator
How heavy a vest to start with, plus a safe progression.
Which Weighted Vest? Quiz
Answer three questions, get matched to the right vest.
Weighted-Vest Walking Plan Builder
A multi-week weighted-walking plan built around your level.
Beginner Walking Plan Builder
A free 8-week beginner walking plan built around your week.
Camp
2 tools
Hike
5 tools
Hiking Water Calculator
How much water to carry for the distance and the heat.
Backpack Size Selector
What size pack (in liters) your trip actually needs.
Backpacking Base-Weight Builder
Add up your pack base weight and see where to cut.
Hiking Layering Advisor
What to wear on the trail, from temperature, effort, wind, and rain.
Outdoor Shoe Finder
Five questions match you to the right outdoor shoes, men's and women's.
Travel
5 toolsNational Park Pack Planner
A park, month, activity, and trip-length packing brief for all 63 national parks.
National Park Finder
Which national park should you visit? Answer four questions.
National Park Pass Calculator
Is an America the Beautiful pass worth it for your 2026 trip?
Carry-On Size Checker
Will your bag fit? Check it against airline size limits.
Airline Power-Bank Rules Checker
Convert mAh to Wh and check current airline power-bank rules.
New tools ship regularly. In the meantime, browse our fitness gear or read how we research and rate.