CalculatorFlux was built on a simple idea: everyone deserves access to free, accurate calculators, without having to wade through ads, paywalls, or outdated information.
We're a small team of developers, writers, and subject-matter experts who care deeply about the details. Whether it's making sure our Illinois paycheck calculator uses the exact 2025 IRS brackets, or that our A1C calculator follows the ADA's official ADAG formula. Accuracy is never an afterthought.
All payroll calculators are reviewed by a licensed CPA and updated within two weeks of any IRS or state tax authority announcement. We use the official IRS Publication 15-T for federal withholding and each state's department of revenue for state rates.
Health calculators use published formulas from recognized medical authorities (ADA, WHO, CDC, AHA). Each calculator includes a clear disclaimer that it is for educational purposes only and is not a substitute 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.
Contact Us →