Model Your Financial Future
with Confidence
Deterministic calculations. AI-powered interpretation. Open formulas you can verify. Built for people who want to understand their numbers, not just see them.
How EstiNest Works
Two layers working together: deterministic math for accuracy, AI for interpretation and insight.
Enter Your Numbers
Input your financial scenario. All calculations run client-side in your browser. Your data never leaves your device.
Get Deterministic Results
Standard financial formulas produce precise outputs. Every formula is published and cited. No black boxes.
AI Analyzes Patterns
GPT-4o-mini interprets results, detects risk patterns, flags anomalies, and suggests optimization strategies.
Calculations are deterministic. The math is always the same. AI only interprets the output — it never modifies the formula.View methodology →
Popular Calculators
Open formulas. Cited data. Instant results.
Mortgage Payment
Calculate your monthly mortgage payment including principal, interest, taxes, insurance, and PMI.
Calculate 📅Amortization
View your complete mortgage amortization schedule showing how each payment is split between principal and interest.
Calculate 🔄Refinance
Determine if refinancing your mortgage makes sense by comparing costs, savings, and break-even timeline.
Calculate 🏡Affordability
Find out how much house you can afford based on your income, debts, down payment, and interest rates.
Calculate 💳Loan Payment
Calculate monthly payments for any type of loan including auto, personal, and student loans.
Calculate 📈Compound Interest
See how your money grows over time with compound interest, recurring contributions, and optional inflation adjustment.
Calculate 🎯Debt Payoff
Compare avalanche and snowball debt payoff strategies with detailed timelines.
Calculate 🧾Income Tax
Estimate your federal income tax with 2024 brackets, deductions, and effective rate.
Calculate 🏖️Retirement Projection
Advanced retirement planner with Social Security estimates, inflation-adjusted projections, and withdrawal strategy analysis using the 4% rule.
Calculate 🤔Opportunity Cost
Calculate the true cost of any financial decision by comparing it against investing that money instead.
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Built on Transparency
No black boxes. Every formula published. Every assumption stated. Every limitation disclosed.
Open Formulas
Every calculator displays its exact mathematical formula. No proprietary black boxes.
Cited Sources
Formulas sourced from IRS, SSA, BLS, CFPB, FRED, CDC, HUD data.
Client-Side Only
All math runs in your browser. Your financial data never touches our servers.
Stated Assumptions
Every simplifying assumption is documented so you can judge applicability.
Beyond Calculation
Every result includes AI-powered interpretation. Wally explains what your numbers mean, detects risk patterns, flags anomalies, and suggests optimization strategies.
Free: 3 AI analyses/month. Pro: Unlimited. AI provides educational interpretations only.
🧠Anomaly Detection
Automatically flags inputs outside typical ranges
🛡️Risk Pattern Analysis
Identifies financial risk combinations in your scenario
💡Smart Suggestions
Specific parameter changes to improve your outcome
🔮Predictive Scenarios
Auto-generates what-if scenarios based on your inputs
Unlock the Complete Platform
Unlimited AI analyses, interactive sensitivity sliders, scenario comparison, PDF/CSV export, and ad-free experience.
Plans start at $7.42/month. Cancel anytime. 30-day money-back guarantee.
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Educational Use Only — EstiNest provides estimates for informational purposes only and does not constitute financial, tax, legal, or medical advice. Always consult qualified professionals. Full disclaimer.