Sensor to notify if weight goes under threshold

Hi, I searched but didn’t find what I think I need.

I need a sensor that tells me when the weight of something goes too low.
For instance, my teenager is responsible for feeding our dogs.
He has a really bad habit of not telling me we’re low on food until we’re out.
I would like to be notified when the food bin weighs less than say, 8 lbs so I can order more (or even better, have it populate in Grocy)

I am still pretty new to HA and a lot of the terminology still confuses me, but as long as I have a general direction I can figure most things out.

Thanks in advance.

Two options that I can think of, both require some DIY:

  1. Load cell
  2. Strain gauge

There are a few projects here using the above sensors for bed occupancy detection.

Perfect. As long as I know what I should be searching for, I should be good. I found a lot of bed sensor posts but I don’t think they really fit my purpose, as the weights are much higher but thank you for giving me a starting point.
My husband is going to be delighted when I no longer text him at 4PM asking him to stop by Publix for dog food.

Your help led me here :heart_eyes: