CalculatorFlux was built on a simple idea: practical calculators should be free to use, explain their assumptions, and avoid unnecessary sign-up barriers.
Founded in 2025 by Hassaan Rasheed, CalculatorFlux is an independent project. Calculators are developed and maintained in this project, with assumptions documented and primary sources linked where rules are time-sensitive.
Whether a tool estimates payroll deductions or converts blood glucose to an estimated A1C, we aim to show the method, state important limitations, and link primary sources on source-sensitive pages.
Payroll calculators identify their tax-year assumptions and provide estimates for common withholding scenarios. Visitors should verify time-sensitive figures with the IRS, state authority, or a qualified professional.
Health calculators use published reference methods where applicable and state their scope and limitations. They are educational tools, not diagnoses or substitutes for professional medical advice.
Financial calculators use standard industry formulas. For retirement and FIRE calculators, we cite our assumptions (market return rate, inflation) so users can adjust their own expectations.
Material calculators are verified against industry standards and building code references. We include recommended waste percentages from the National Association of Home Builders.
Every CalculatorFlux calculator runs entirely in your browser. Your numbers never touch our servers. When you're calculating your salary, blood sugar, or retirement savings, that's your personal information and it should stay yours. We don't log calculations and we don't sell data.
Found an error? Want to suggest a new calculator? We're always listening.
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