How long it takes to boil water with a backpacking stove depends on the fuel type, stove power, and other environmental factors. Stoves like the Jetboil Flash are said to bring water to a boil in as little as 100 seconds, and other popular stove brands like MSR can usually boil water in around 2 minutes. Most backpacking stoves on the market should be able to boil 1 liter of water in under 10 minutes, but most will be closer to 5 minutes or less.