Examples
Examples
Try the starting example
- Batches of ONE product: lot ID, units, last usable date
- A,5,2026-10-21 B,10,2026-10-25
- First consumption date
- 2026-10-20
- Planned daily consumption (same units)
- 2
- Days to simulate
- 5
- Units consumed
- 10
- Units expired unused
- 1
- Closing stock units
- 4
- First shortage date
- None in horizon
- Unserved planned consumption units
- 0
Try another scenario
- Batches of ONE product: lot ID, units, last usable date
- A,5,2026-10-21 B,10,2026-10-25
- First consumption date
- 2026-10-20
- Planned daily consumption (same units)
- 2
- Days to simulate
- 10
- Units consumed
- 12
- Units expired unused
- 3
- Closing stock units
- 0
- First shortage date
- 2026-10-26
- Unserved planned consumption units
- 8
Calculation method
Calculation method
Units consumed
At each day start discard batches whose last-usable date is before today, then consume first-expiring eligible stock.
Units expired unused
Sum discarded quantities; entered dates are inclusive last-usable dates.
Closing stock units
Stock remaining after the final simulated day.
First shortage date
First day whose requested consumption cannot be met, or None in horizon.
Unserved planned consumption units
Sum daily requested consumption minus actual consumption.
Symbols and units
- a
- Batches of ONE product: lot ID, units, last usable date
- b
- First consumption date
- c
- Planned daily consumption (same units)
- d
- Days to simulate
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- A FEFO stock ledger for one interchangeable product in one common unit. Last-usable dates and daily quantities are supplied by you; this does not establish food safety, shelf life or reorder lead time.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
OpenStax: arithmetic and geometry ↗
Background reading; this does not imply endorsement or independent review of SumFizz.