Wh to Amp Calculator

Converting Watt-hours (Wh) to Amperes (Amps) calculates the electric current draw required by a system over a given operating duration.

1. 1
   Select Circuit Phase: Choose DC, AC Single-Phase, or AC Three-Phase.
2. 2
   Enter Watt-Hours (Wh): Input the stored energy in Watt-hours.
3. 3
   Enter Voltage (V): Input system operating voltage (e.g. 12V, 24V, 120V).
4. 4
   Enter Time (Hours): Input discharge runtime duration in hours.

Converting Amperes (Amps) to Watt-hours (Wh) calculates total energy consumption when electric current flows across a circuit for a specified duration.

1. 1
   Select Circuit Phase: Choose DC, AC Single-Phase, or AC Three-Phase.
2. 2
   Enter Current (Amps): Input electric current in Amperes.
3. 3
   Enter Voltage (V): Input system voltage (e.g. 12V, 220V, 240V).
4. 4
   Enter Time (Hours): Input operational duration in hours.

Watt-hours (Wh) measure total stored energy, whereas Amperes (Amps) measure electric current rate. Dividing stored energy by operating voltage and discharge time in hours yields electric current: Amps = Wh ÷ V ÷ Hours.

Real-Life Wh to Amp Sizing Scenarios

Scenario 1: Deep Cycle Marine Battery Sizing
A 1,200 Wh marine battery operating at 12V DC discharges over a 5-hour period:
Amps = 1200 Wh ÷ 12 V ÷ 5 Hours = 20 Amps (Charge capacity = 100 Ah)

Scenario 2: Off-Grid Solar Power System Sizing
A 2,048 Wh solar battery operating at 24V DC discharges over an 8-hour period:
Amps = 2048 Wh ÷ 24 V ÷ 8 Hours = 10.67 Amps (Charge capacity = 85.33 Ah)

Step-by-Step Sizing Guide & Formulas

Step 1: Identify energy (Wh = 1200 Wh), voltage (V = 12V), and runtime (Hours = 5 h).

Step 2: Calculate Ampere-hours (Ah): 1200 ÷ 12 = 100 Ah.

Step 3: Divide by runtime: 100 ÷ 5 = 20 Amps.

Final Answer: 1200 Wh at 12V operating over 5 hours delivers 20 Amps.

Converting Amperes (Amps) to Watt-hours (Wh) calculates total electrical energy by multiplying current, system voltage, and operating hours: Wh = Amps × V × Hours.

Real-Life Amps to Wh Sizing Scenarios

Scenario 1: Household Appliance Load Sizing
A 10 Amp single-phase appliance operates at 220V AC for 5 hours (PF = 1.0):
Wh = 10 Amps × 220 V × 5 Hours = 11,000 Wh (11.0 kWh)

Scenario 2: RV Deep Cycle Battery Capacity Sizing
A 100 Ah 12V deep-cycle battery provides energy storage:
Wh = 100 Ah × 12 V = 1,200 Wh (1.2 kWh)

Step-by-Step Sizing Guide & Formulas

Step 1: Identify current (Amps = 1 A), voltage (V = 240V), and runtime (Hours = 1 h).

Step 2: Multiply parameters: Wh = 1 × 240 × 1 = 240 Wh.

Final Answer: 1 Amp at 240V operating for 1 hour consumes 240 Wh.

The lookup table below details calculated current draw (Amps) and capacity (Ah) across standard Watt-hour (Wh) battery ratings at 12V, 24V, and 48V DC systems:

The lookup table below details calculated Watt-hours (Wh) across common electric current (Amps) and capacity (Ah) ratings across various operating voltages: