Average Cost Calculator

Calculate a new average purchase price from existing holdings and an additional buy.

Note: An investment reference calculation. Reflect fees, taxes, exchange rates, and fill methods yourself, and do not use it as the sole basis for investment decisions.

Category: Calculators

When to use?

Use it to calculate a new average purchase price after buying more stock or crypto. It also helps find the break-even point after averaging down.

How to use

  • Enter your existing quantity and average price.
  • Enter the additional quantity and purchase price.
  • The new average price and total quantity are calculated.

Input Explanation

Enter the quantity and average price of your current holdings, plus the quantity and price of the additional purchase.

Calculation Basis

New average = (existing qty × existing average + added qty × added price) ÷ (existing qty + added qty).

Usage Examples

  • Check average after buying more - Enter the added quantity and price to calculate the new average.
  • Review averaging down - See how much the average drops when buying more of a fallen holding.
  • Find the break-even price - Use the new average to find the break-even price.

Examples

  • Existing 100 @ 50,000 + added 50 @ 40,000 → new average 46,667 (total 150)
  • Existing 10 @ 80,000 + added 10 @ 100,000 → new average 90,000 (total 20)

Cautions

  • Fees and taxes are not included. For real investment decisions, consult your brokerage app or an expert.
  • This is a simple estimate from your inputs and a general formula; verify officially before any real or commercial use.

Guides

How the average is calculated

It adds the existing and additional purchase amounts, then divides by the total quantity for the new average purchase price.

Reflecting fees and taxes

If there are fees, taxes, or exchange rates, reflect them in the purchase price so the figure is closer to your real cost basis.

FAQ

Are fees and taxes included?

The base calculation uses the purchase amount; reflect fees and taxes in the price yourself.

How is the average calculated?

Add the existing and additional purchase amounts, then divide by the total quantity.

Does averaging down always lower the average?

Only when the added price is below the existing average. Buying higher raises the average.

Can I use it for partial selling?

This tool is for buy-average calculation. Selling does not change the average of the remaining quantity.

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