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Session cost
Estimate how much a charging session will cost using your selected rate and charging inputs.
EV Charging Cost & Savings
Understand EV charging costs instantly.
WattWise helps EV drivers estimate session cost, compare charging rates and understand miles added before they plug in.
No account required. Charging sessions and tariff preferences stay on your device.
Simple charging decisions.
WattWise focuses on clear, factual EV charging estimates without unnecessary dashboards or supplier assumptions.
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Charging details
See energy required, charge duration, estimated completion time, miles added and cost per mile.
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Rate comparison
Compare full-session costs across Off-Peak, Peak, Public and Custom charging rates.
Designed for clarity.
A calm, premium interface built around the question EV drivers ask most: what will this charge cost?
Privacy
WattWise is designed as a local-first EV charging calculator. It does not require an account to estimate charging costs.
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Local preferencesYour charging rates, settings and recent sessions are stored on your device.
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No account requiredYou can use WattWise without creating an account or signing into a service.
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No live supplier dataWattWise uses the values you enter. It does not claim live tariff or supplier intelligence in Version 1.