Editorial Standards

Calcura is a small, independent project. We publish free calculators and reference tools across finance, cooking, time, fitness, DIY, and AI topics. This page explains how that work gets done — what we cite, how we test, and how we correct mistakes.

We don't require accounts, we don't collect calculation data, and we don't sell anything. Hosting costs are covered by a small number of display ads on pages with full reference content.

Our editorial principles

• Cite primary sources. When a number or formula comes from an authority (the IRS, the Federal Reserve, CFPB, USDA, NIH, CDC, ISO, IANA, ACSM), we link directly to that authority rather than paraphrasing a secondary source.
• Show the math. Every calculator that has a formula shows it. If you can't see how a number was derived, you shouldn't trust it.
• No fabricated statistics. We won't attribute a statistic to an organization without a link to their publication. If a claim can't be cited, we rewrite it as a general principle or remove it.
• Honest caveats. Financial and health calculations depend on assumptions. Where those assumptions matter (tax jurisdiction, return variability, individual medical context) we say so plainly rather than implying the number is universal.
• No advice. Calcura's tools help you do arithmetic. They are not financial, medical, legal, or professional advice.

How a calculator gets built

1. Formula research. We identify the authoritative formula for the calculation and link to it. For example, our TDEE calculator uses the Mifflin-St Jeor equation (PubMed 2305711); our mortgage calculator uses the standard amortization formula documented by the Consumer Financial Protection Bureau.
2. Reference test cases. We compare our output against at least two independent sources — typically an authoritative calculator (bank, government, academic) and a hand-worked example — before publishing.
3. Edge-case checks. Zero inputs, very large inputs, rounding near boundaries, leap years, timezone transitions, currency edge cases. If a calculator produces bad output in a corner case, we either fix it or document the limitation.
4. Publication. Every calculator ships with an explanation of the formula, a worked example, common mistakes to avoid, and links to related tools.

How we update

Tax tables, interest rates, and published benchmarks change. Calculators that depend on them are reviewed at least annually, and immediately when a change is material. Each page carries a “Last reviewed” date so you can see when the content was last checked.

How to report an error

If a calculation looks wrong — or if we've cited something we can't support — email support@calcura.io with the calculator URL, the inputs you used, the result you got, and what you expected. We investigate every report and correct confirmed errors within 48 hours.

What Calcura is not

Calcura does not provide financial, tax, medical, legal, or professional advice. Our tools are reference utilities. Before making decisions that materially affect your money, health, or legal standing, consult a qualified professional.