Calcxo.

Trust

Sources & Methodology

Trustworthy calculators rely on trustworthy inputs. This page lists the data we use, where it comes from, how often it's refreshed, and the assumptions that go into every result.

Last updated

Where our data comes from

Calcxo draws on three categories of sources:

  • Formulas — drawn from standard textbooks, peer-reviewed papers, and official guidance (e.g. the WHO for BMI, the SEC and consumer-finance regulators for APR/APY, national tax authorities for tax brackets).
  • Reference data — currency rates, inflation series, statutory rates, and similar values come from recognized providers and central banks. Each calculator that depends on live data names its provider on the page.
  • Worked examples — taken from primary publications when available, and re-derived by our team otherwise. Every example is reproducible from the formula shown on the page.

Update cadence

How often we refresh depends on how the data behaves:

  • Live rates (currency, market data): updated on demand at the time of calculation, with the timestamp shown alongside the result.
  • Periodic data (tax brackets, statutory thresholds, inflation): reviewed at least annually, and whenever a relevant authority publishes a change.
  • Stable formulas (compound interest, BMI, area conversions): reviewed on a 12-month cycle for presentation and clarity even when the math doesn't change.

Each page shows its own Last updated date so you can see exactly when it was last verified.

How we choose references

We prefer the most authoritative source available for a given topic — typically a regulator, standards body, or peer-reviewed publication. When multiple credible sources disagree, we explain the disagreement on the page rather than picking one silently. Outdated, paywalled-without-substitute, or low-quality sources are not used.

Assumptions we use

Calculators are simplifications. Where an assumption could meaningfully change the result, we make it explicit on the page. Common defaults across Calcxo:

  • Interest is compounded as stated (annually, monthly, daily) — never assumed.
  • Currency conversions use the mid-market rate at the moment of calculation; bank spreads and fees are not included.
  • Health calculators (BMI, calorie needs) report population averages and are not a substitute for personal medical advice.
  • Tax calculators reflect headline rates only; they do not model deductions, credits, or local surcharges unless the page says so.

Limits and what we don't claim

Our results are educational and informational. Calcxo does not provide financial, medical, legal, or tax advice. For decisions that materially affect your money or health, consult a qualified professional who knows your situation.