About QuickUse
Our mission
QuickUse Calculator is a bilingual library of fast, accurate online calculators for personal finance, taxation, real estate, health, and math. We built it because the biggest calculator sites do one thing well — generic US-focused math, packaged in cluttered pages — and stop there. Brazilian taxation, US-state-specific payroll, and the comparisons between the two were left to a long tail of specialized blogs that frequently get the math wrong.
Our goal is to be the calculator you trust enough to bookmark — bilingual from day one (English plus Brazilian Portuguese), source-cited for every regulatory input, decimal-precision for every financial calculation, and reviewed by a named human before publication. The differentiator is not the math — most calculators get the math directionally right. The differentiator is the paper trail.
What makes us different
Bilingual EN + PT-BR with full localization
Universal calculators ship in both languages with human-edited prose, regional currency formatting, and locale-appropriate examples. Country-specific calculators (IRPF, 401(k)) live only in the locale where they apply, with their slug naturally untranslated. No machine-translated middle ground.
Decimal-precision math for financial calculators
Every dollar, real, and percentage is computed using arbitrary-precision decimal math via decimal.js. We never use JavaScript floats for money. The error from binary floating-point compounds over long periods in financial domains — we refuse to inherit that class of bug.
Yearly verification of tax and regulatory tables
Every regulatory file on the site has a "last verified" date and a "next review" date. Each annual update fetches the official source via web search rather than trusting model memory or last year's value. The git history records the diff. Read more on our methodology page.
Named authors and credentialed reviewers
Every calculator and post has a named author and reviewer linkable to a profile page. Editorial team handles are disclosed openly. We do not use AI-generated headshots presented as real people. The "Reviewed by" badge on each calculator is the visible E-E-A-T signal — every page has a human responsible for it.
Open methodology and source citations
Every calculator cites primary sources at the bottom of the page. The methodology page documents how we build, validate, and update content. If we do something different from what is documented there, the documentation is wrong and we want to fix it.
The editorial team
Every calculator and post on the site is written or reviewed by one of the people or team handles below. Click through for full bios, expertise, and credential disclosures. Pen names and team handles are openly declared as such — we do not present them as fictional individuals.
How we make money
Today, QuickUse is supported by display advertising via Google AdSense. We are honest about that because how a site makes money should be disclosed up-front, not buried in a privacy policy.
Three rules govern how advertising works on the site: ads are loaded only after the page content has rendered (never blocking the calculator widget); ad units have reserved height to prevent layout shift (cumulative layout shift below 0.05 is a strict target); and pages on emotionally-loaded topics (financial hardship, certain health calculators) skip ads. Future affiliate links — for example, contextual partnerships with brokerages on investment calculators — will be marked rel="sponsored" and disclosed in the page itself, not stuffed into the footer fine print.
We do not accept paid editorial. We do not feature partner products in calculators. Calculator output never prioritizes a partner over precision. The wall between revenue and editorial is the only thing that makes a research tool useful, and we treat it as non-negotiable.
What we do with your data
Calculations happen entirely in your browser. We never see the numbers you enter. Favorites and history are stored on your device via localStorage and IndexedDB, not on our servers. We collect anonymous traffic analytics — pages visited, country, browser, load times — via Vercel Analytics and (with consent) Google Analytics 4 for AdSense compliance. The full details are in our privacy policy.
Cookie consent uses Google's Funding Choices banner with consent mode v2, which means analytics and ads default to a privacy-preserving mode until you actively opt in. You can re-open the consent banner any time via the "Manage cookies" link in the footer.
Reach us
For bug reports — a calculator returning a value that disagrees with an authoritative source — email contact-us@quickusecalculator.com with the URL, the inputs, the value returned, and the value you expected with its source. We aim to triage cited-number reports within 48 hours.
For collaboration — if you are a CFP, CPA, or a Brazilian contador with active CRC registration interested in being a named reviewer for calculators in your domain — reach out via the same address or the contact page.
Our story
QuickUse was started in late 2025 to fill a specific gap — a bilingual reference for personal-finance and tax math that worked equally well for someone living in Brazil and someone living in the United States. The site went live with a small set of universal calculators (compound interest, BMI, mortgage) and quickly expanded into Brazilian labor-law calculators — IRPF, rescisão, FGTS, salário-líquido — that were the immediate frustration.
As of 2026 the catalog covers more than fifty calculators across finance, real estate, health, math, and US/BR taxation, with a growing blog of explainers and pillar guides. The roadmap focuses on (a) deepening editorial substance per calculator, (b) onboarding credentialed contributors as named reviewers in fiscal and health domains, and (c) adding pillar comparators (Brazil-vs-US payroll, refinance scenarios, retirement framework decisions) where existing tools split the topic poorly.