Weighted Average Cost Calculator (Stock/Crypto)

Calculate the weighted average purchase price across two buy lots.

Methodology reviewed 2026-07-27. See our review process.

Formula and method

This calculator uses the values you enter and applies the calculation immediately in your browser. The main output formulas are:

  • Average cost per unit: (qty1*price1+qty2*price2)/(qty1+qty2)
  • Total invested: qty1*price1+qty2*price2

Some formulas are undefined for certain input combinations, such as division by zero, equal x-values in a slope calculation, or logarithms of non-positive numbers. In those cases the live tool reports that the result is undefined instead of displaying Infinity or NaN.

Examples

  • Example: with Lot 1 quantity = 10, Lot 1 price = 100, Lot 2 quantity = 5, Lot 2 price = 120, this calculator returns Average cost per unit = 106.6667, Total invested = 1600.
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  • Try related finance tools when your next step needs another conversion or calculation.

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Frequently asked questions

Is Weighted Average Cost Calculator (Stock/Crypto) free to use?

Yes. Weighted Average Cost Calculator (Stock/Crypto) is completely free, has no usage limit, and does not require an account, email, or API key.

Does Weighted Average Cost Calculator (Stock/Crypto) store or upload my data?

No. Weighted Average Cost Calculator (Stock/Crypto) calculates everything locally in your browser. Nothing you type is sent to a server or stored by SpecWhale.

How accurate is Weighted Average Cost Calculator (Stock/Crypto)?

Weighted Average Cost Calculator (Stock/Crypto) uses a standard formula (see the Method section above for the exact expression). For high-stakes financial, medical, or legal decisions, confirm the result with a professional or an authoritative source before relying on it.

Can I embed Weighted Average Cost Calculator (Stock/Crypto) on my own website?

Yes. Use the "Embed this tool" snippet on this page to add a free, working copy of Weighted Average Cost Calculator (Stock/Crypto) to your own blog post or page.

SEO and sharing notes

This page has a single clean canonical URL, descriptive metadata, breadcrumb structured data, and internal links to related tools. Supported calculators and converters can also copy a prefilled share link without changing the canonical index URL.