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Making a major financial decision? Stop juggling spreadsheets and browser tabs. Decision Lab gives you a library of scenario-based calculators designed to answer real questions — not just crunch numbers.
RUN EXPERIMENTS, NOT JUST CALCULATIONS
Each calculator is built around a real decision: Should I rent or buy? Is an EV cheaper than gas over 5 years? When can I actually retire? Enter your numbers, see results instantly, and save them as experiments you can revisit anytime.
11 CALCULATORS ACROSS 5 CATEGORIES
Housing: Mortgage, Rent vs Buy, Home Affordability
Vehicle: Auto Loan, Car Total Cost of Ownership, EV vs Gas
Wealth: Compound Interest, FIRE Number, Retirement Age
Family: Child Cost Estimator
Career: Real Hourly Wage
SEE WHAT ACTUALLY MATTERS
Every result highlights the Key Drivers — the 3 inputs that influence your outcome the most. Stop guessing which assumptions matter and focus your attention where it counts.
COMPARE OPTIONS SIDE BY SIDE
Rent vs Buy, EV vs Gas, and Car TCO calculators let you enter two scenarios and see a clear winner with charts over time.
YOUR ASSUMPTIONS, YOUR BASELINE
Set your expected investment return, inflation rate, home price growth, and more in one place. Every new experiment starts from your personal baseline — no re-entering the same numbers.
SAVE, DUPLICATE, AND ITERATE
Save experiments with custom titles and notes. Duplicate any result and tweak one variable to see how it changes the outcome. Your financial thinking evolves — your tool should too.
FULLY OFFLINE & PRIVATE
No account required. No data leaves your device. Every calculation runs locally.
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What's New in Decision Lab
1.1.0
April 10, 2026
What's New in Version 1.1.0 Multilingual Support - Added full localization for Traditional Chinese, Simplified Chinese, Japanese, and Korean - Calculator defaults, field labels, results, and accessibility labels are now localized - Vehicle units and assumptions adapt to your region - New in-app language switcher in Settings New Design - Refreshed UI with a precision-focused, data-dense aesthetic inspired by professional analytics tools Bug Fixes - Fixed a crash when deleting experiments - Fixed a crash on the experiments list - Fixed tap handling issues caused by the ad banner
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