Methodology

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Editorial principles

  1. Formula first, copy second. Before publishing a calculator page, the math function is written in TypeScript and covered by unit tests.
  2. Verifiable source. Every legal constant cites the norm or official site where it was published.
  3. In-browser calculation. User data is not sent to a server to process.
  4. Visible disclaimer. Every calculator with legal or tax consequence shows a clear reference-only notice.

Legal sources by country

Ecuador

  • Labor Code — basis for 13th salary, 14th salary, vacation, reserve fund.
  • Social Security Law and IESS resolutions — personal and employer contribution rates.
  • Internal Tax Regime Law — VAT, ISD, withholdings, e-invoicing.
  • Ministerial SBU agreement — official minimum wage per year.

Payment gateway fees

  • PayPal: merchant fees per region from paypal.com (reviewed at least yearly).
  • Stripe: stripe.com/pricing per country.
  • MercadoPago: official fee documentation per country.

Automated tests

Each calculator has a calc.test.ts with cases:

  • Typical case (normal user).
  • Edge case (zero, very large numbers, decimals).
  • Officially documented case (when an example is published by the authority).
  • Rounding (we verify rounding matches the legal method).

Deploy pipeline runs tests before publishing. If a constant changes and a test breaks, the calculator does not deploy until the expected case is fixed.

Update cycle

  • January: annual constant review (SBU, tax brackets, gateway fees).
  • Quarterly: exchange rates, international commissions.
  • On any bug report: targeted review.

Constant versioning

Constants store their effective year in source:

// src/lib/calculators/ec-iess/calc.ts
export const IESS_RATES_2026 = {
  employeeGeneral: 0.0945,
  employerGeneral: 0.1115,
  reserveFund: 0.0833,
};

This lets us serve a historical rate when a user computes a past period.

Errors and correction

Confirmed formula errors are fixed in under 48 business hours, with a regression test added, and a footer note on the calculator when impact is relevant.