Basic Disaster Supply KitWater (one gallon per person per day for several days, for drinking and sanitation), food (at least one multi-day supply of non-perishable food), battery operated or hand crank radio and NOAA weather radio with tone alert, flashlight, first aid kit, additional batteries, whistle (for help signal). You should have enough food to eat comfortably for three days and include a variety of light, nutritious and high-calorie options. Freeze-dried meals, high-calorie energy bars, and MREs are a good place to start increasing your food supply. You're probably working hard or under stress, and your body needs enough energy to stay focused and strong.
Between 2000 and 2500 calories a day is a safe bet for adults. Being a survivor means adapting to any situation with the right survival tools, tips and tricks. A number of sites will recommend slightly different items for your essential survival kit, but the items listed above are the most commonly used. It mentions water filtration tablets, but nothing about a container in which to put water to purify it.
I would recommend including at least one 1 liter collapsible water bottle on the list (one per person). I would add a 24 to 48 hour backup charger for smartphones. Today's phones have GPS tracking devices. The chargers are small and light.
The gears chosen for your kit are the tools that will help you survive and thrive in any situation. Generally speaking, the more outdoor survival skills you master, the fewer items you'll need in your survival kit. Different locations, climates, experience levels, and group sizes require different survival and customization equipment. While there's no way to know how long you'll need to survive on your own after a natural disaster or other emergency, planning a minimum of three days of survival is a good starting point.