Blackout Math.Power Calculator

Blackout Math

Power Calculator for Real Blackouts

When power is unstable, guessing becomes expensive.

Wrong battery choices, unrealistic expectations, and incorrect calculations lead to wasted money and failed setups.

Blackout Math is not a generic calculator.

It is a practical decision-making tool designed for real power outages — helping you understand how long your power will actually last and which battery truly fits your needs.

No ideal numbers. No marketing promises.

Only realistic calculations for real conditions.

Know how long your power will last

Configure your battery type, capacity, and voltage — and Blackout Math will:

• calculate usable energy in Wh and kWh

• account for safe depth of discharge for each battery chemistry

• factor in inverter efficiency and real losses

• show realistic operating limits

No overestimation.

No dangerous assumptions.

See the real impact of your devices

Add any household appliances — lights, routers, laptops, refrigerators, boilers, heaters.

Specify power, quantity, and usage time, and the app will instantly:

• calculate real energy consumption

• show each device’s impact on total load

• determine actual runtime — not theoretical values

You’ll know exactly when power runs out.

Real charging time — not guesses

Blackout Math considers battery chemistry and charging limits to provide:

• accurate charging time estimates

• warnings about unsafe charging currents

• charging power based on voltage × amperage

• state-of-charge calculations from any starting level

No unrealistic “0 to 100%” promises.

Complex energy concepts, explained clearly

Blackout Math helps you understand:

• why usable energy is always lower than nominal

• what depth of discharge really means

• how inverter efficiency affects runtime

• how to choose batteries for real-world usage

No engineering background required.

Built for clarity and speed

Clean inputs, instant calculations, intuitive sliders, and light & dark themes — designed for fast, stress-free decisions when time matters.

Perfect for:

• planning during blackouts

• choosing portable power stations (EcoFlow, Bluetti, Anker)

• estimating backup time for apartments and houses

• selecting batteries for solar and backup systems

• analyzing and optimizing home energy usage

Blackout Math is built for real conditions.

It helps you avoid costly mistakes and make confident decisions — even under pressure.

Less guessing.

More certainty.

Better energy decisions.