Weighted Average Calculator

Enter the values the weighted average form asks for and the result is computed here, in the page, with no sign-up and no upload. Change one field at a time to see how sensitive the weighted average figure is to that assumption.

Basic Calculator
GPA Calculator
Financial Average

Enter Values and Weights

Course Grades and Credits

Investment or Cost Data

Embed tool Add this tool to your website Get embed code

Add this calculator to a related page with a visible HeyCal source link.

Instant results No signup required Standard formulas Free to use

Frequently Asked Questions about Weighted Average Calculator

How do I sanity-check the weighted average result?

Rerun the calculator with a known example and compare it against the figure you expect; then swap back to your own numbers.

Which weighted average inputs change the outcome most?

Adjust one field at a time. The figure that shifts the result hardest is the assumption worth double-checking before you rely on it.

How do I calculate my weighted GPA for a semester with different credit hours?

Enter each course’s percentage grade and its credit hours (or units) into the GPA tab. The tool multiplies each grade by the credits to get grade points, sums all grade points, then divides by total credits. For example, an 85% in a 3-credit course gives 255 grade points. A 90% in a 4-credit course gives 360 points. Total points (615) divided by total credits (7) equals a weighted GPA of approximately 3.47 on a 4.0 scale. The tool shows this step-by-step and converts the final percentage to a letter grade automatically.

Can I use this tool for weighted average inventory cost calculation in accounting?

Yes. Switch to the “Financial Average” tab. Enter each purchase price in the “Price/Cost ($)” field and the corresponding quantity in the “Quantity/Shares” field. The tool calculates the weighted average price per unit, total quantity, and total value. This matches the Weighted Average Cost (WAC) method used in perpetual and periodic inventory systems. It’s also correct for dollar-cost averaging in investment portfolios.

Does the weighted average calculator work if my weights are percentages that don't add up to 100?

Absolutely. The basic calculator accepts any numerical weights. If you enter weights of 10, 20, and 30 (summing to 60), the tool still calculates correctly: it sums the products of (value × weight) and then divides by the sum of weights (60). The result is mathematically identical to normalizing percentages. This is useful when weights represent raw points, frequencies, or any other importance measure.

What’s the difference between a weighted average and a simple average?

A simple average adds all values and divides by the count—treating every value equally. A weighted average multiplies each value by a predetermined weight before summing, then divides by the total weight. Use simple averages for things like “average temperature” where each day is equal. Use weighted averages for grades (final exams matter more than quizzes), inventory costs (larger purchases matter more), or portfolio returns (more invested shares matter more). The calculator on this page handles both by letting you set weights; if all weights are equal, it functions as a simple average.