Source guide for CalculatorShelf units and formulas

Storage calculators

RAID, disk-capacity, binary/decimal unit, transfer-rate, surveillance-storage, memory-card, and VRAM tools use deterministic arithmetic plus storage-industry terminology checks. Binary-vs-decimal unit conversions are called out where they change the answer.

Home-project calculators

Home-project pages are estimating aids. Material formulas use visible geometric assumptions; cost and safety-sensitive pages remain planning aid unless current product data, code constraints, and professional boundaries are clear.

Pool and water calculators

Pool and chemical pages are conservative planning aids. Product labels, test-kit readings, local codes, and qualified pool guidance override every default. Safety-sensitive pages stay conservative until label constants are clear.

Shipping calculators

Shipping pages expose dimensional, weight, mileage, and fee assumptions rather than claiming live quotes. Real carrier tariffs, customs requirements, fuel surcharges, seasonality, and provider quotes can override defaults.

Lifestyle calculators

Household pages use simple area, count, or sizing heuristics. They are written to make the assumption visible instead of implying exact fit, exact weather, or exact product performance.

Sports calculators

Running pace tools use official road-race distance constants for common events and simple time-divided-by-distance arithmetic. See World Athletics marathon distance, World Athletics half marathon distance, and NIST SI length units.

Sports sizing tools are starting-point aids. Manufacturer size charts, terrain, skill level, and personal fit checks override generalized formulas.

Business calculators

Business tools are held back until formulas, examples, and context notes are specific enough for public use.

How source quality shapes calculator pages

Calculator pages are strongest when they have deterministic math, crawlable default output, visible formula notes, an updated date, calculator-specific validation, clear assumptions, examples, limitations, FAQs, and links to nearby tools.

Safety-sensitive calculators use conservative language and point users back to product labels, qualified professionals, local code, or authoritative references when a generic web calculation should not be the final decision.

Rocket equation and standard gravity

These references support the named formula, unit relationship, or decision boundary. Calculator inputs remain visible so a reader can replace every example assumption.

• NASA Glenn ideal rocket equation
• NIST CODATA standard gravity

GPA and course weighting

These references support the named formula, unit relationship, or decision boundary. Calculator inputs remain visible so a reader can replace every example assumption.

• College Board 4.0-scale GPA method
• College Board weighted and unweighted GPA guidance

Pallet volume and unit conversion

These references support the named formula, unit relationship, or decision boundary. Calculator inputs remain visible so a reader can replace every example assumption.

• NIST SI length units
• CalculatorShelf pallet volume formula and limits

Translation purchasing and entered pricing terms

These references support the named formula, unit relationship, or decision boundary. Calculator inputs remain visible so a reader can replace every example assumption.

• Institute of Translation and Interpreting client guide
• CalculatorShelf translation cost formula and limits

Electricity use and lighting cost

These references support the named formula, unit relationship, or decision boundary. Calculator inputs remain visible so a reader can replace every example assumption.

• U.S. EIA electricity measurement guide
• CalculatorShelf lighting energy formula and limits