Calculate Voltage Across a Component
Find the voltage drop across a resistor from current and resistance.
💡 Ohm's law: V = I × R. Power adds P = V × I. Knowing any two lets you derive the rest — handy for sizing resistors, checking LED current, or working out heat dissipation.
Voltage Drop tips
Enter current and resistance to get the voltage dropped across that component (V = I × R).
In a series circuit the voltage drops add up to the supply voltage — handy for voltage dividers.
Long thin wires have resistance too; significant drop there means you need a thicker gauge.
使い方
なぜ私たちのツール？
Also check out…
Size a Current-Limiting Resistor for an LED
Work out the resistor value an LED needs from supp
Calculate Power Dissipation (Watts)
Find how many watts a component dissipates so you
Solve Ohm's Law Homework
Check circuit problems by entering any two known v
Estimate Current Draw from a Battery
Find the current a load pulls so you can estimate