📈 MPS Calculator (Marginal Propensity to Save)
Calculate the marginal propensity to save (MPS), the share of extra income people save rather than spend, plus the related spending multiplier.
What MPS measures
The marginal propensity to save (MPS) is the fraction of each extra dollar of income that a household saves instead of spending. It is a core concept in macroeconomics used to understand consumption behavior and the size of the spending multiplier.
The formula
MPS is calculated as change in savings ÷ change in income. Since every extra dollar of income is either spent or saved, MPS and the marginal propensity to consume (MPC) always add up to 1, so MPS also equals 1 − MPC. The spending multiplier, 1 ÷ MPS, shows how an initial change in spending can ripple through the economy to produce a larger total change in output.
This calculator is for general economics education and planning. Real-world consumption and saving behavior can vary by income level, taxes, and other factors not captured in this simple model.