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Cost per watt hour calculator

Cost per watt hour is the price you are quoted divided by rated capacity in watt hours. Type in the models and prices you are looking at below and this tool ranks them. WattFort publishes no prices, so every price here is one you enter yourself.

By The WattFort TeamUpdated Runs in your browser, nothing is sent anywhere

Enter your own local prices for accuracy. Your choice is remembered on this device.

Rates updated 13 Nov 2026

Models and prices you are comparing

The starting rows are unbranded examples. Replace the names, prices and capacities with the models and quotes you are looking at.

Your ranking

Person carrying a portable power station by its handle

How the calculator works

  • Cost per watt hour = price divided by rated capacity in watt hours.
  • Cost per kilowatt hour = cost per watt hour × 1,000. We show it because some listings and home batteries are priced per kWh.
  • Rows are ranked from the lowest cost per watt hour to the highest. Only rows with a price and a capacity above zero are ranked.

Lower cost per watt hour is not automatically better. On the maker spec sheet, check warranty length, battery chemistry and cycle life, continuous and surge watts, charging speed, ports, weight and whether the capacity can grow later. A small station often shows a higher cost per watt hour because the inverter, case and ports cost much the same whatever the battery size. Size the station first with our runtime calculator or power station finder, then use this tool to judge value among models that already fit.

Frequently asked questions

How do I calculate cost per watt hour for a power station?

Divide the price you would pay by the rated capacity in watt hours. A station priced at 500 with 1,000 Wh of capacity costs 0.50 per Wh, or 500 per kWh. This tool does that for each model you enter and ranks them, cheapest stored energy first.

Is lower cost per watt hour always better?

Not always. A very cheap watt hour can come with a shorter warranty, older battery chemistry, fewer cycles, lower continuous or surge output, fewer ports, slower charging, or a weight you cannot move. Use cost per watt hour to spot value, then check those points on the maker spec sheet.

Why does WattFort not list model prices here?

WattFort publishes no model prices, because prices change often and vary by country. This calculator therefore ranks only the prices you type in yourself from quotes or listings you are looking at. The starting rows are unbranded examples, not real model prices.

Which currency does it use?

You can enter and rank prices in US dollars, pounds, euros, Canadian dollars, Australian dollars, Indian rupees or Pakistani rupees using the currency selector at the top. Amounts you type are converted to US dollars for storage at cent level precision, then shown back in your currency, so typing a small amount counts exactly. Rates come from ExchangeRate-API (open.er-api.com), and the backup rates built into this page are from 13 November 2026. Treat them as a guide only.

Should I compare cost per watt hour or cost per kilowatt hour?

They are the same ranking at a different scale. Cost per kilowatt hour is cost per watt hour multiplied by 1,000. Watt hours suit portable stations because their capacities are listed in watt hours, so this tool leads with cost per Wh and also shows cost per kWh.

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