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Pet Food Duration Calculator

How long a bag or case of pet food lasts, and when to reorder.

Enter values

Results update as you type.

Result

Bag lasts

40 days

Dry food is best used within about six weeks of opening — buy a size you will finish in that time.

In weeks
5.71
Daily use for all pets
300 g
Reorder after
35 days
Bags per year
9.1
Food per year
109.5 kg
Food remaining at reorder
1.5 kg

About the Pet Food Duration Calculator

How long a bag or case of pet food lasts, and when to reorder.

Also known as: how long will dog food last, pet food supply calculator, food bag duration, when to reorder pet food.

How to use this calculator

  1. Enter bag or case size, daily amount, number of pets, reorder lead time.
  2. The result updates instantly as you type — press Calculate (or Enter) at any time.
  3. Review the breakdown shown under the main result.
  4. Use Copy result or Share to save the answer or send a link with your inputs.

Formula

days = bag size ÷ daily amount for all pets

Worked example

Using the values pre-filled in the calculator above:

  • Bag or case size = 12 kg
  • Daily amount = 300 g
  • Number of pets = 1
  • Reorder lead time = 5

the calculator returns:

  • Bag lasts: 40 days
  • In weeks: 5.71
  • Daily use for all pets: 300 g
  • Reorder after: 35 days