Financial Clarity for Everyone
EstiNest is an AI-powered financial decision support platform that provides free, transparent, and privacy-first calculators for mortgage payments, loan estimates, compound interest, retirement projections, taxes, budgeting, and more.
Our Mission
Financial decisions are among the most consequential choices people make, yet the tools available to analyze them are often opaque, ad-heavy, or designed to funnel users toward specific products. EstiNest was built on a fundamentally different premise: financial modeling should be transparent, accessible, and free from conflicts of interest.
Every formula we use is published openly on our Methodology page. Every data source is cited with a direct link to the authoritative institution — the IRS, the Consumer Financial Protection Bureau, the Bureau of Labor Statistics, the Social Security Administration, the CDC, and others. We do not use proprietary algorithms that hide how your numbers are calculated. If you want to verify our math, we encourage it.
We believe that when people understand the formulas behind their financial decisions, they make better choices. Our role is not to give financial advice — we are explicit that we do not — but to give you the tools and explanations to reason more clearly about mortgages, investments, taxes, loans, retirement, and everyday math.
What We Offer
44+ Free Calculators
Covering 11 categories including mortgage, loan, investment, tax, retirement, health, business, education, everyday, and conversion calculators. Every calculator uses standard, peer-reviewed formulas with full documentation of assumptions and limitations.
AI-Powered Explanations
Our AI layer, powered by GPT-4o-mini, interprets your pre-computed results in plain English. It explains what the numbers mean, highlights what matters most, and suggests optimization strategies. The AI never computes or modifies calculations — it only explains them. Read our AI Transparency documentation for full details.
Privacy-First Architecture
All calculator computations run entirely in your browser. Your financial inputs — income, loan amounts, investment balances — are never transmitted to our servers. The only data we store server-side is your email address (for account purposes) and subscription status. We hash email addresses and comply with GDPR data minimization principles. See our Privacy Policy for complete details.
Cited Sources & Open Formulas
Every formula links to its authoritative source. Mortgage calculations reference the CFPB and Freddie Mac. Tax calculations cite IRS Revenue Procedures. Health metrics link to CDC and NIH publications. We document all assumptions and proactively disclose limitations. Browse our complete Methodology.
Our Approach to Trust
Trust is earned through transparency, not claims. Here is specifically how we build trust with our users:
Published Formulas
Every mathematical formula is displayed on the calculator page and documented on our Methodology page. You can verify our calculations independently.
Authoritative Citations
Data sources include the IRS (tax brackets), SSA (Social Security), BLS (inflation data), CFPB (mortgage rules), CDC (health metrics), HUD (housing guidelines), SBA (business formulas), and FRED (economic data).
Documented Assumptions
Every simplifying assumption is stated explicitly. If a calculator assumes fixed interest rates, monthly compounding, or standard deductions, we say so.
Known Limitations
We proactively disclose what our calculators do not model: volatility, ARM rate resets, state taxes, AMT, investment fees, and other factors. This is not typical, but we believe it is right.
Client-Side Execution
Calculator inputs never leave your device. We use your browser as the compute engine. Our servers handle only authentication and subscription management.
Educational Framing
We consistently state that EstiNest is for educational and informational purposes only. We do not provide financial, tax, legal, or investment advice. We encourage consulting qualified professionals for significant decisions.
Technology & Security
EstiNest is built on modern, secure infrastructure designed for performance and privacy:
- •Cloudflare Pages & Workers — Deployed on Cloudflare’s global edge network for fast load times worldwide. TLS 1.3 encryption, DDoS protection, and Web Application Firewall included.
- •Next.js (React) — Modern frontend framework with static generation for optimal performance. All calculator UIs are server-rendered for fast initial load and SEO.
- •Stripe & PayPal — PCI-DSS Level 1 compliant payment processing. We never store credit card information. Payments are processed entirely by Stripe and PayPal.
- •Google Sign-In — Authentication via Google OAuth. We receive only your email address and name; we never see your Google password.
- •Content Security Policy — Strict CSP headers prevent cross-site scripting and data exfiltration. We whitelist only the specific domains required for payments, analytics, and authentication.
Our Subscription Model
All 44+ calculators are free to use, forever. We believe financial literacy tools should be accessible to everyone. Our Pro subscription unlocks advanced features for users who need deeper analysis:
- • Unlimited AI explanations for every calculator result
- • Scenario comparison — run side-by-side what-if analyses
- • Sensitivity analysis sliders to explore variable ranges
- • PDF and CSV export for professional use
- • Ad-free experience
We offer a 30-day refund guarantee. You can cancel anytime from your dashboard with one click. There are no cancellation fees and no hidden friction. If EstiNest Pro doesn’t deliver value, we will refund you — email support@estinest.com.
Contact Us
We value feedback and are always working to improve. Whether you have a feature request, a bug report, a question about our methodology, or a concern about your data, we want to hear from you.
- General inquiries: support@estinest.com
- Subscription & billing: support@estinest.com
- Privacy & data requests (GDPR): support@estinest.com
You can also visit our Contact page for additional options.
⚠ Important Disclaimer
EstiNest is an educational financial modeling platform. It does not provide financial, tax, legal, investment, or medical advice. Calculator results are estimates based on user-provided inputs and documented assumptions. Actual outcomes may differ due to market conditions, fees, taxes, regulatory changes, and individual circumstances not modeled.
Always consult qualified professionals (financial advisor, CPA, attorney, physician) before making significant decisions based on calculator results.
Last updated: February 22, 2026 · Covering 44+ calculators across 11 categories