Pure formulas
Each result comes from a deterministic TypeScript function.
Methodology
Useful estimates, with the working shown.
We keep every calculator small, inspectable and honest about what it can—and cannot—tell you.
Browser-only inputs
Your calculator values never need to leave your device.
No hidden data feed
Changing tariffs and prices are entered by you.
Our calculation standard
Every public tool separates its inputs, formula and result. Units are displayed next to each field, reasonable ranges prevent obvious mistakes, and the result includes assumptions that matter to the decision. Formula functions are covered by automated tests and run independently of the page design.
Currency is formatted in Indian rupees, electricity is measured in kilowatt-hours, and metric or commonly used Indian household units are preferred. We do not silently convert a monthly value into a daily value without showing the relationship in the result.
Why we ask for your tariff
Electricity pricing varies by state, distribution company, connection type, consumption slab, taxes and surcharges. Equipment quotes and solar benefits also change. A single hard-coded value would quickly become misleading, so our calculators use the rate you enter from a recent bill or verified source.
Planning estimate, not professional advice
Electrical safety, structural suitability, battery protection, AC heat loads and solar installation design require qualified professionals and, where applicable, local approvals.
Limits we state openly
Household equipment rarely operates at one fixed power level. Refrigerators cycle, inverter ACs modulate, batteries age, and solar output changes with cloud, shade and temperature. Our tools model these effects only when an input explicitly represents them.
Simple payback calculations exclude financing, opportunity cost, maintenance, component replacement, degradation and future tariff changes unless the calculator says otherwise. They are best used to compare scenarios on the same assumptions.
Corrections and review
We review formulas when a tool changes and retest the affected examples before release. Policy-linked information is not embedded unless it has an official source and review date. The current subsidy estimator intentionally asks the visitor to supply the verified rate and cap.