calc.engineer / PCB & Electronics / Ohms Law

Ohms Law v1.0.0

Solves Ohm's Law and the power equation given any two of four electrical quantities: voltage (V), current (I), resistance (R), and power (P). Uses V=IR, P=VI, P=I^2R, and P=V^2/R to derive the missing two values. Fundamental for every circuit design task: sizing resistors, estimating current draw, checking power dissipation, and verifying component ratings. Chain into led_resistor for LED circuits or voltage_divider for bias networks.

← from voltage_dividerfeeds led_resistor →feeds voltage_divider →feeds trace_width →
Voltage in volts (V). Provide exactly 2 of the 4 parameters.
Current in amps (A). Provide exactly 2 of the 4 parameters.
Resistance in ohms. Provide exactly 2 of the 4 parameters.
Power in watts (W). Provide exactly 2 of the 4 parameters.
Fill in the inputs and Compute to see the structured result.

From an agent (MCP) or the API

curl -X POST https://calc.engineer/api/ohms_law \
  -H "Content-Type: application/json" \
  -d '{"voltage_v": …, "current_a": …, "resistance_ohm": …}'

MCP: connect to https://calc.engineer/mcp and call ohms_law.

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