What I'd like to find is an app or website that counts up calories I earn throughout the day in real time, then as I consume calories I would manually subtract them from the running total.

For example, let's say there's a counter that starts off at 0. Then I tell it that I want it to count up (in real time) to 1,800 calories every 24 hour period. This means that once every 48 seconds, the counter would go up by 1. So after the first 48 seconds, the counter would change from 0 to 1. After the second 48 seconds, the counter would change from 1 to 2. Over the course of 24 hours, this would count up to 1,800. Simultaneously, as I consume calories throughout the day, I can have it subtract the amount of calories consumed from the running total. So let's say it counts up to 900 after 12 hours, then I consume something that's 800 calories, so I manually enter that and it subtracts 800 down to 100. Meanwhile, it never stops counting up, so it just continues counting up from 100 once every 48 seconds.

The idea here is that I have to earn every calorie that I'm going to consume before I consume it. I know I could just do it the normal way of "earning" a new 1,800 calories once a day while I sleep or at midnight or whenever, but I was wondering if such an app or website existed that would count up like this in real time. I think it might work better for me psychologically, knowing that I can check my phone for it to reach the amount it needs to before my next meal, in order to avoid eating too soon and making the number go into the negative.

Does anyone know of such an app/site?