# Accuracy & Methodology At TheCalculatorsHub, we believe that trust is only earned through transparency. This page explains every layer of our accuracy architecture. --- ## 01. Decimal-Precision Mathematics All financial, medical, and engineering calculations use **Decimal.js** — a high-precision decimal arithmetic library. Standard JavaScript arithmetic has a well-known flaw: `0.1 + 0.2 = 0.30000000000000004`. This silent error compounds over multi-step calculations like mortgage amortization or medication dosages. **What this means for you:** Our numbers are mathematically correct, not floating-point approximations. --- ## 02. Expert Audit & Verification Process Every calculator is linked to a **verified domain expert** — a licensed professional engineer, certified financial analyst, PhD academic, or licensed healthcare professional. **The Audit Process:** 1. The formula is documented in LaTeX (visible in the "Calculation Logic" section of each tool) so the math is fully auditable. 2. The expert reviews the formula against the published standard (e.g., ASHRAE for HVAC, IRS publications for tax, AKC guidelines for veterinary tools). 3. A `lastVerified` timestamp is recorded and exposed in the tool's JSON-LD schema for search engine freshness signals. 4. High-traffic YMYL tools are re-verified every 6–12 months or whenever the underlying standard changes. --- ## 03. Freshness & Content Currency YMYL (Your Money or Your Life) content must be current. Stale financial or medical data causes real-world harm. **Our Freshness Policy:** - Every tool exposes `dateModified` in its JSON-LD, corresponding to the most recent expert verification. - Tax rate, loan, and health-related tools are prioritized for annual review after regulatory updates. - The ExpertBar displayed on each tool page shows the verification date publicly so users can evaluate data currency. --- ## 04. YMYL Compliance & Disclaimer Policy Google classifies TheCalculatorsHub as a **YMYL** (Your Money or Your Life) site. We take this classification seriously. Every YMYL tool displays a contextual disclaimer reminding users that results are estimates and professional consultation is recommended. Disclaimer language is category-specific: - **Veterinary / Biology / Health** → Consult a licensed veterinarian or healthcare professional - **Finance / Mortgage / Tax** → Consult a qualified financial advisor - **Construction / Engineering** → Consult a licensed structural engineer Our tools are designed to **augment** — not replace — expert judgment. --- ## 05. External Source Citations Where applicable, our tools cite **high-authority external sources** to prove the math is grounded in established standards. Examples: American Kennel Club (AKC), IRS Publications, NCBI/PubMed, ASHRAE Standards, Government Housing Data. External source links appear in the "Sources & References" section of qualifying tool pages, always marked with `rel="nofollow noopener noreferrer"`. --- ## Our Technology Stack | Layer | Technology | |---|---| | Framework | Next.js 15 | | Precision Math | Decimal.js | | Database | PostgreSQL (Neon) | | ORM | Prisma 7 | | Hosting | Vercel Edge | --- *Last reviewed: March 2026. If you spot an error, please use our contact form to report it.*