TheCircuitDogOhm's Law Calculator
Use Ohm’s law to solve voltage, current, resistance or electrical power in an ideal resistive DC circuit.
Calculate →Tools library
Electronics Calculators
Fast interactive calculations, worked examples and engineering caveats in one place.
Circuit Fundamentals
Voltage Divider Calculator
Find the output of a two-resistor divider. Add an optional load resistance to estimate how the load pulls the output down.
Calculate →LED Resistor Calculator
Size a series resistor for one or more LEDs in a string. The calculator estimates the resistor value and power dissipation.
Calculate →Series and Parallel Resistor Calculator
Enter resistor values in ohms, separated by commas or spaces, and select a series or parallel connection.
Calculate →Analog Design
RC Time Constant Calculator
Estimate first-order resistor-capacitor timing, including the 63.2% charge time and the approximate −3 dB low-pass corner.
Calculate →Series and Parallel Capacitor Calculator
Enter capacitances in microfarads. This tool computes ideal series and parallel capacitance.
Calculate →LC Resonant Frequency Calculator
Find the natural resonant frequency of an ideal inductor-capacitor combination.
Calculate →Op-Amp Closed-Loop Gain Calculator
Calculate closed-loop gain for a standard inverting or noninverting op-amp resistor network.
Calculate →Power Design
LDO Power Dissipation Calculator
A quick screening tool to estimate heat in a linear regulator as it drops voltage at a specified output current.
Calculate →Battery Runtime Calculator
Estimate how long a battery can power a roughly constant load after usable capacity and conversion losses.
Calculate →Inductor Energy Calculator
Compute the approximate energy stored in an inductor as a function of inductance and current.
Calculate →PCB & Layout
PCB Trace Resistance Calculator
Estimate the DC copper resistance, voltage drop and resistive heating along a straight PCB trace.
Calculate →Data Conversion
ADC Resolution and LSB Calculator
Calculate the ideal unipolar ADC step size and an approximate code for a particular input voltage.
Calculate →Signals & RF
Decibel Gain and Loss Calculator
Convert a positive voltage or power ratio into decibels. Select the right formula for what you are comparing.
Calculate →Digital & Timing
PWM Duty Cycle Calculator
Find PWM duty cycle and switching frequency from the pulse on-time and total period.
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