Food Waste Cost Calculator
Estimate how much wasted food could be costing you each week, month and year from your grocery spend, waste percentage or itemised wasted-food list.
Calculate your food waste cost
Use a quick percentage of your grocery spend, or add known wasted-food items such as bread, fruit, veg, leftovers or unused ingredients.
Optional itemised waste list
Add rough weekly values for food you often throw away. This is separate from the percentage estimate and helps you spot the biggest waste areas.
| Food or category | Estimated weekly wasted cost | Action |
|---|---|---|
Enter your grocery spend and estimated waste percentage to see the result.
How the food waste calculator works
The calculator starts with your normal weekly grocery spend and multiplies it by the percentage you think is wasted. It then scales the result into monthly and yearly estimates.
Weekly waste cost = weekly grocery spend × waste percentage
Monthly waste cost = weekly waste cost × 52 ÷ 12
Yearly waste cost = weekly waste cost × 52
The target waste percentage shows the potential saving if you reduce food waste. For example, cutting waste from 10% to 5% on an £80 weekly shop saves about £208 a year.
Food waste cost examples
| Weekly shop | Waste estimate | Weekly waste | Yearly waste |
|---|---|---|---|
| £60 | 5% | £3.00 | £156 |
| £80 | 10% | £8.00 | £416 |
| £120 | 15% | £18.00 | £936 |
These are simple estimates. Your real cost depends on what you buy, what you throw away, portion sizes, meal planning, storage and whether leftovers are reused.
What to include in your estimate
Simple ways to reduce food waste cost
Small changes can reduce the wasted part of your grocery spend without needing a strict budget. Start with the most repeated waste category rather than trying to fix everything at once.
- Plan meals around food already in the fridge or freezer.
- Buy smaller amounts of fresh food if it regularly spoils.
- Freeze bread, meat, sauces and leftovers before they go off.
- Use the Grocery Cost Calculator to compare a planned shop with your usual spend.
- Use the Recipe Scaler to cook the right number of portions.
Limitations of the estimate
This calculator is useful for quick budgeting, but it cannot know exactly what was edible, what was unavoidable waste, or whether an item was partly used. Treat the result as a practical estimate, not an exact audit.
Food waste cost FAQs
How do I calculate food waste cost?
Multiply your weekly grocery spend by the percentage you estimate is wasted. For example, £80 × 10% = £8 wasted per week.
How do I calculate yearly food waste cost?
Multiply the weekly waste cost by 52. If waste costs £8 per week, the yearly estimate is £416.
Should I include unavoidable waste?
You can, but it is usually more useful to separate unavoidable waste such as bones, shells or peelings from edible food that could have been used.
Can this calculator tell me exactly how much I waste?
No. It gives an estimate based on the numbers you enter. For a more accurate result, track food thrown away over a typical week.