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Weighted-Average Inventory Calculator

Calculate weighted-average unit cost, cost of goods sold and ending inventory for two purchase layers.

Runs locally

Inputs and results stay in this browser. Currency symbols are illustrative; use any consistent currency.

Weighted-average unit cost$10.89
Cost of goods sold$1,306.67
Ending inventory$653.33

Understand Weighted-average inventory

One idea, three depths

Choose how deeply to explain Weighted-average inventory

Weighted-average inventory: Calculate weighted-average unit cost, cost of goods sold and ending inventory for two purchase layers.

Age 5Explain it to a 5-year-oldStart with a picture

Imagine using Weighted-average inventory to answer this question: calculate weighted-average unit cost, cost of goods sold and ending inventory for two purchase layers? Enter First layer units, First unit cost, Second layer units, and 2 other inputs; the calculator shows Weighted-average unit cost. For example: 100 units at $10 and 80 at $12 produce a weighted-average cost of $10.89 per unit. The answer tells you Weighted-average unit cost.

Age 15Explain it to a 15-year-oldConnect it to the formula

The weighted-average method blends purchase layers into one unit cost. Periodic and perpetual systems can produce different results when purchases and sales alternate. The rule is Average unit cost = Total cost available ÷ units available. Its input values are First layer units, First unit cost, Second layer units, Second unit cost, Units sold, and the main result is Weighted-average unit cost. For example: 100 units at $10 and 80 at $12 produce a weighted-average cost of $10.89 per unit.

CollegeExplain it at college levelState the model precisely

This calculator evaluates one accounting relationship within a consistent entity, currency, reporting period and recognition policy. The implemented relation is Average unit cost = Total cost available ÷ units available, evaluated from First layer units, First unit cost, Second layer units, Second unit cost, Units sold to produce Weighted-average unit cost. The weighted-average method blends purchase layers into one unit cost. Periodic and perpetual systems can produce different results when purchases and sales alternate. Recognition, measurement, tax, consolidation, foreign-currency and disclosure rules may require adjustments under the accounting framework that applies to the entity.

What this accounting tool does

Calculate weighted-average unit cost, cost of goods sold and ending inventory for two purchase layers.

Why the relationship works

The weighted-average method blends purchase layers into one unit cost. Periodic and perpetual systems can produce different results when purchases and sales alternate.

The accounting formula

Average unit cost = Total cost available ÷ units available

Inputs and period consistency

This model uses First layer units, First unit cost, Second layer units, Second unit cost, Units sold. Use the same reporting period, currency, entity boundary and accounting policy for every input.

What the result means

The primary output is Weighted-average unit cost; supporting outputs include Cost of goods sold, Ending inventory. Trace each amount back to the relevant ledger or statement line before relying on it.

Worked accounting example

100 units at $10 and 80 at $12 produce a weighted-average cost of $10.89 per unit.

Limits of this compact model

The calculator teaches one relationship. Recognition, measurement, tax, consolidation, foreign-currency and disclosure rules may require additional adjustments under the framework that applies to the entity.

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Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations

Standards, reading and academic references

Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.

Principles of Accounting, Volume 1: Financial Accounting

Read the free OpenStax financial accounting textbook
Cite this book
APA 7
Franklin, M., Graybeal, P., & Cooper, D. (2019). Principles of accounting, volume 1: Financial accounting. OpenStax. https://openstax.org/books/principles-financial-accounting/pages/1-why-it-matters
MLA 9
Franklin, Mitchell, et al. Principles of Accounting, Volume 1: Financial Accounting. OpenStax, 2019, https://openstax.org/books/principles-financial-accounting/pages/1-why-it-matters.
Chicago author-date
Franklin, Mitchell, Patty Graybeal, and Dixon Cooper. 2019. Principles of Accounting, Volume 1: Financial Accounting. Houston, TX: OpenStax. https://openstax.org/books/principles-financial-accounting/pages/1-why-it-matters.

OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.

Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS

These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.

Organizational author: MW SysArc. Published:. Canonical page:https://accounting.mwsysarc.com/weighted-average-inventory-calculator.

APA 7

MW SysArc. (2026, July 21). Weighted-Average Inventory Calculator. MW SysArc Tools. https://accounting.mwsysarc.com/weighted-average-inventory-calculator

MLA 9

MW SysArc. “Weighted-Average Inventory Calculator.” MW SysArc Tools, 21 July 2026, https://accounting.mwsysarc.com/weighted-average-inventory-calculator. Accessed 26 Aug. 2026.

Chicago 17

MW SysArc. “Weighted-Average Inventory Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 26, 2026. https://accounting.mwsysarc.com/weighted-average-inventory-calculator.

Harvard

MW SysArc (2026) ‘Weighted-Average Inventory Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://accounting.mwsysarc.com/weighted-average-inventory-calculator (Accessed: 26 August 2026).

BibTeX and RIS records

BibTeX

@misc{mwsysarc_weighted_average_inventory_accounting_2026,
  author = {{MW SysArc}},
  title = {Weighted-Average Inventory Calculator},
  howpublished = {MW SysArc Tools},
  year = {2026},
  url = {https://accounting.mwsysarc.com/weighted-average-inventory-calculator},
  note = {Published July 21, 2026; accessed August 26, 2026}
}

RIS

TY  - ELEC
AU  - MW SysArc
TI  - Weighted-Average Inventory Calculator
T2  - MW SysArc Tools
PY  - 2026
DA  - 2026-07-21
Y2  - 2026-08-26
UR  - https://accounting.mwsysarc.com/weighted-average-inventory-calculator
N1  - Published July 21, 2026
ER  -

Clear answers

Frequently asked questions

What does the Weighted-average inventory do?

Calculate weighted-average unit cost, cost of goods sold and ending inventory for two purchase layers.

How does the Weighted-average inventory work?

The calculator applies Average unit cost = Total cost available ÷ units available. The weighted-average method blends purchase layers into one unit cost. Periodic and perpetual systems can produce different results when purchases and sales alternate.

What can I learn from the Weighted-average inventory?

You will connect First layer units, First unit cost, Second layer units, Second unit cost, Units sold to Weighted-average unit cost, then see how the relationship belongs in the accounting process.

Does MW SysArc receive or store what I enter?

No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.

How should I use the result?

Use the result as an educational or reconciliation reference. Confirm the reporting period, accounting policy and source records before relying on it.

Last reviewed . Calculations tested .

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