Probably about 2 or 3 months on what's in the fridge/freezer/cupboards, but I've only got about a week's worth of fresh stuff. It wouldn't be fancy or fab, but it would meet our needs.
I have a stockpile of things like tinned toms/beans/fruit/veg/lentils/chick peas and other beans/fish/meat/condensed soup and dried onions, also a whole load of jam/chutney/pickle/fruit pie filling that I made last autumn, 2 big sacks of bread flour from the mill along with a lot of yeast, about 10kg plain and SR flour, about 4kgs of spelt and rye flour, extra sugar, honey, syrup, cocoa powder, oil, tea, coffee, dried milk, stock cubes, herbs, spices etc. About 10kgs pasta and the same of rice and another 10kgs dried beans, 3kgs lentils, 2kgs oats, a pile of dried milk, a case of peanut butter, some shelf stable solid veg oil (for baking), long life fruit juice, bottles of high juice....
The freezer has probably 15 or 20 kilo bags of veg as well as mince of various hues, pork shoulder, lamb shoulder, mutton, sausages, cooked chicken, cooked turkey, mixed game, a couple of rabbits, fish, prawns, scallops, mussels, homemade sausagemeat.
We would struggle for eggs, yoghurt, cheese and sandwich meat, but other than that, we would manage. The trick is rotating through it so that we use stuff and then replace it. It's all a bit embarrassing, really, but I have a complete fear of running out of money and not being able to buy food (it used to happen when my OH was drinking.) So, I buy a little extra every month and stockpile, you can hardly move in the hall cupboard for huge plastic boxes full of stuff and the hut has boxes full of jam etc..