Macroeconomics
Open Economy Multiplier Calculator
Estimate the spending multiplier when taxes and imports create additional leakages.
Inputs and results stay in this browser. Currency symbols are illustrative; use any consistent currency.
Understand Open-economy multiplier
One idea, three depths
Choose how deeply to explain Open-economy multiplier
Open-economy multiplier: Estimate the spending multiplier when taxes and imports create additional leakages.
Age 5Explain it to a 5-year-oldStart with a picture
Imagine using Open-economy multiplier to answer this question: estimate the spending multiplier when taxes and imports create additional leakages? Enter Marginal propensity to consume, Marginal tax rate, Marginal propensity to import, and 1 other input; the calculator shows Open-economy multiplier. Try changing one number and watch what happens to Open-economy multiplier. The answer tells you Open-economy multiplier.
Age 15Explain it to a 15-year-oldConnect it to the formula
Taxes and imports reduce successive rounds of domestic spending, making the open-economy multiplier smaller than the simplest closed-economy multiplier. The rule is Multiplier = 1 ÷ [1 − MPC × (1 − tax rate) + marginal propensity to import]. Its input values are Marginal propensity to consume, Marginal tax rate (%), Marginal propensity to import, Initial spending change (bn), and the main result is Open-economy multiplier. Try changing one number and watch what happens to Open-economy multiplier.
CollegeExplain it at college levelState the model precisely
This calculator evaluates a macroeconomics relationship while holding unmodelled conditions constant. The implemented relation is Multiplier = 1 ÷ [1 − MPC × (1 − tax rate) + marginal propensity to import], evaluated from Marginal propensity to consume, Marginal tax rate (%), Marginal propensity to import, Initial spending change (bn) to produce Open-economy multiplier. Taxes and imports reduce successive rounds of domestic spending, making the open-economy multiplier smaller than the simplest closed-economy multiplier. The result depends on comparable definitions, units, populations and time periods. It estimates a relationship; it does not establish causation or replace current primary data.
The economic question
Estimate the spending multiplier when taxes and imports create additional leakages.
Why this relationship is useful
Taxes and imports reduce successive rounds of domestic spending, making the open-economy multiplier smaller than the simplest closed-economy multiplier.
Inputs that must be comparable
- Marginal propensity to consume (minimum 0, maximum 1).
- Marginal tax rate (minimum 0, maximum 100) measured in %.
- Marginal propensity to import (minimum 0, maximum 1).
- Initial spending change measured in bn.
Use one market, firm, population and time period throughout; mixing definitions can make a correctly calculated number economically meaningless.
The model
Multiplier = 1 ÷ [1 − MPC × (1 − tax rate) + marginal propensity to import]
From inputs to output
The calculator combines Marginal propensity to consume, Marginal tax rate, Marginal propensity to import, Initial spending change and reportsOpen-economy multiplier together with Estimated GDP change. Change one assumption at a time to identify what actually drives the estimate.
How to read Open-economy multiplier
Read the sign, magnitude, unit and period together. The result quantifies the relationship in “estimate the spending multiplier when taxes and imports create additional leakages”; it does not by itself prove that one input caused another.
Where interpretation can fail
Do not use the result when the input definitions, units or formula assumptions do not match the real situation. This is an educational model, not financial, investment, tax or policy advice; verify material decisions against primary data and professional guidance.
Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations
Standards, reading and academic references
Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.
Principles of Economics 3e
Read the free OpenStax economics textbookCite this book
- APA 7
- Greenlaw, S. A., Shapiro, D., & MacDonald, D. (2022). Principles of economics 3e. OpenStax. https://openstax.org/books/principles-economics-3e/pages/1-introduction
- MLA 9
- Greenlaw, Steven A., et al. Principles of Economics 3e. OpenStax, 2022, https://openstax.org/books/principles-economics-3e/pages/1-introduction.
- Chicago author-date
- Greenlaw, Steven A., David Shapiro, and Daniel MacDonald. 2022. Principles of Economics 3e. Houston, TX: OpenStax. https://openstax.org/books/principles-economics-3e/pages/1-introduction.
OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.
Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS
These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.
APA 7
MW SysArc. (2026, July 21). Open Economy Multiplier Calculator. MW SysArc Tools. https://economics.mwsysarc.com/macro/open-economy-multiplier
MLA 9
MW SysArc. “Open Economy Multiplier Calculator.” MW SysArc Tools, 21 July 2026, https://economics.mwsysarc.com/macro/open-economy-multiplier. Accessed 31 Aug. 2026.
Chicago 17
MW SysArc. “Open Economy Multiplier Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://economics.mwsysarc.com/macro/open-economy-multiplier.
Harvard
MW SysArc (2026) ‘Open Economy Multiplier Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://economics.mwsysarc.com/macro/open-economy-multiplier (Accessed: 31 August 2026).
BibTeX and RIS records
BibTeX
@misc{mwsysarc_open_economy_multiplier_2026,
author = {{MW SysArc}},
title = {Open Economy Multiplier Calculator},
howpublished = {MW SysArc Tools},
year = {2026},
url = {https://economics.mwsysarc.com/macro/open-economy-multiplier},
note = {Published July 21, 2026; accessed August 31, 2026}
}RIS
TY - ELEC
AU - MW SysArc
TI - Open Economy Multiplier Calculator
T2 - MW SysArc Tools
PY - 2026
DA - 2026-07-21
Y2 - 2026-08-31
UR - https://economics.mwsysarc.com/macro/open-economy-multiplier
N1 - Published July 21, 2026
ER -Clear answers
Frequently asked questions
What does the Open-economy multiplier do?
Estimate the spending multiplier when taxes and imports create additional leakages.
How does the Open-economy multiplier work?
The calculator applies this formula: Multiplier = 1 ÷ [1 − MPC × (1 − tax rate) + marginal propensity to import]. Taxes and imports reduce successive rounds of domestic spending, making the open-economy multiplier smaller than the simplest closed-economy multiplier.
What can I learn from the Open-economy multiplier?
It helps you explore the relationship described by this tool: Estimate the spending multiplier when taxes and imports create additional leakages. Change one input at a time to observe how it affects the result.
Does MW SysArc receive or store what I enter?
No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.
How should I use the result?
Use the result as an estimate or educational aid. Check important financial, business or policy decisions with qualified sources and current data.
Last reviewed . Calculations tested .