Weighted Moving Average Forecast Calculator
A weighted moving average is a simple forecast that emphasises selected observations. Use consistent periods and choose weights before reviewing the forecast to avoid cherry-picking.
How to use this calculator
- Enter the oldest observation using the units shown beside the field.
- Enter the oldest observation weight using the units shown beside the field.
- Enter the middle observation using the units shown beside the field.
- Review the calculated values and check that the assumptions match your scenario.
- Change one input at a time when comparing scenarios so you can see which assumption drives the result.
Formula and assumptions
Forecast = Σ(valueᵢ × weightᵢ) / Σ(weightᵢ).
- This simple forecast assumes the selected observations and weights are relevant to the next period. Seasonality, sudden shifts and data quality are not modelled.
- The result is computed from the values you provide; it does not fetch external rates, live account data or local rules.
Worked examples
Worked example
Values 82, 87 and 93 with weights 1, 2 and 3 produce a weighted forecast of 89.17.
Example inputs: Oldest observation = 82, Oldest observation weight = 1, Middle observation = 87, Middle observation weight = 2.
Compare the displayed output with your own measurements before using it in a decision.
Understanding the result
This simple forecast assumes the selected observations and weights are relevant to the next period. Seasonality, sudden shifts and data quality are not modelled.
Results are estimates based on the stated model. If the situation depends on measured conditions or contractual specifications, use those source values rather than typical assumptions.
Important notes
This simple forecast assumes the selected observations and weights are relevant to the next period. Seasonality, sudden shifts and data quality are not modelled.
Frequently asked questions
What formula does this calculator use?
It uses the method described above: Forecast = Σ(valueᵢ × weightᵢ) / Σ(weightᵢ).
What should I verify before relying on the result?
This simple forecast assumes the selected observations and weights are relevant to the next period. Seasonality, sudden shifts and data quality are not modelled.
Can I compare different scenarios?
Yes. Change the inputs while keeping units and definitions consistent, and record the assumptions used for each scenario.
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Related explanations
Learn the method behind the number or compare the terminology before using the calculator.
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This page provides a calculation tool plus explanatory information so you can understand what the result means and when the underlying method may not fit your situation.