About & Methodology

Monthly cost is your entered token volume × each gateway's own published per-million-token price for the selected model. Prices are checked manually against each gateway's public pricing page and dated (shown on the results page) rather than polled live, and currency conversion uses a live Bank of Russia (CBR) exchange rate.

Costs use each vendor's own published API pricing, checked manually against their public pricing pages and dated on the results page — this calculator does not call vendor APIs to fetch pricing live.

The prices behind the comparison are checked manually against each vendor's own public pricing page and dated; the logic that finds the cheapest covering combination of subscriptions is this calculator's own, applied to those verified prices.

The temperature (−25°F / −15°C) and time (×0.8) adjustments are cross-checked against independent English- and Russian-language cooking sources rather than a single site's rule of thumb.

Combines two independent, widely-known stocking rules of thumb — a metric-converted, size-tiered version of the classic "inches of fish per gallon" guideline, and a surface-area gas-exchange rule — shown side by side rather than blended into one number, since the two can legitimately disagree.

Cost is your own slicer's weight/time estimate (Cura, PrusaSlicer, OrcaSlicer, Bambu Studio all show one) times your filament price and local electricity price, plus an optional printer-amortization term — arithmetic on figures you and your slicer supply, not a third-party pricing database.

Saponification (SAP) values are cross-checked against two independently published soap-making references (The Soap Kitchen's SAP value guide and SoapCalc's oil list) — standard figures used across the soap-making community, not invented for this calculator.

Mixing-ratio math follows your own product's label ratio (by volume or by weight, never silently converted between the two) — the density gap between resin and hardener varies significantly by formulation, per published resin data sheets, so guessing a conversion would silently give the wrong amounts.

Uses real measured ethanol-water mixture density data and mass conservation, not the volume-additive shortcut most online dilution calculators use — mixing ethanol and water measurably shrinks the total volume, which that shortcut ignores.

Uses the standard veterinary RER/DER formula (Resting Energy Requirement = 70 × body weight in kg^0.75, per Kleiber's law) and life-stage multiplier ranges used by veterinary nutrition services and the WSAVA Global Nutrition Committee's guidelines.

Simulates the actual row-by-row installation rather than a flat area/coverage formula, with a safety-margin buffer added on top for cuts and future repairs — standard practice for minimizing material loss.

A quicker, area-based estimate covering the same flooring math as the full Flooring Calculator, for when a row-by-row simulation isn't needed.

Volume-to-weight conversions use typical reference bulk densities for each material (concrete, gravel, mulch, and so on) — labeled explicitly as typical reference values, since a specific product's exact density can differ.

Round bar, round tube, rectangular tube, and sheet use exact geometric volume × density formulas. Angle and channel use a simplified cross-section that treats corners as perfectly square (real rolled profiles have a small fillet radius), typically within about 1-5% of a supplier's catalog weight.

Paintable wall area uses standard deductions for doors (≈1.6 m²) and windows (≈1.5 m²); coverage-per-liter defaults to a typical figure, with an explicit prompt to check your own paint can's label and scale the result if it differs.

Sloped roof area uses standard trigonometry (horizontal footprint stretched by 1/cos(angle)) — exact for a simple single-pitch or gable roof footprint. Complex hip/valley roof geometry is intentionally left out rather than approximated.

Pipe length uses the standard area ÷ spacing formula used across underfloor heating calculators, with the manifold distance added twice (there and back) and a buffer for turns and trimming.

Wall area uses the same perimeter × height formula and door/window deductions as the Paint Calculator, divided by one roll's coverage area and rounded up, since partial rolls aren't sold.

Uses the standard reverse rate-setting formula from freelance business guidance: required gross revenue = (target take-home ÷ (1 − tax rate)) + overhead, divided by your billable hours.

Uses the standard fixed-rate loan amortization formula used across the mortgage industry and financial-math textbooks. It is not a substitute for your lender's exact amortization schedule, which may round or apply payments slightly differently.

Cost is distance × consumption × fuel price, in either imperial (mpg) or metric (L/100km) units — plain unit-consistent arithmetic on the fuel price and consumption figures you enter yourself; the calculator doesn't pull a live fuel price or your car's real-world consumption from anywhere.

Overall diameter, speedometer error, and ground clearance change all follow from standard tire-size geometry (rim diameter plus twice the sidewall height, itself derived from the tire's printed width/aspect-ratio/rim-size code) — the same math any tire-fitment reference uses.

Payload capacity is GVWR minus curb weight; the combined-weight check is your loaded truck weight plus trailer weight against GCWR. Both figures come from your own truck's door sticker or owner's manual — this calculator doesn't look up ratings by vehicle make or model. Tongue/hitch weight, when not entered exactly, is estimated at 10% of trailer weight, the low end of the commonly cited 10-15% range, and shown flagged as an estimate.

The weighted-average and reverse-solver math is standard grade arithmetic. The default percentage-to-letter thresholds shown are a common convention, not a universal standard — there isn't one — and are editable to match your own school's or instructor's scale.

Plan specs and prices are verified manually against each provider's own current pricing page, with the verification date shown on the results page — not a live scrape — and currency conversion uses a live Bank of Russia (CBR) exchange rate.