Electronics & Circuit Tools
Explore the arithmetic behind small direct-current circuit plans with every assumption visible. Solve the relationship between voltage, current and resistance, combine ideal resistors, inspect a loaded voltage divider, size a first-pass LED series resistor and compare battery cells in series and parallel.
These educational calculators do not design or certify a real circuit. Component tolerance, insulation, transient energy, heat, protection, battery chemistry and safe measurement methods require data sheets, appropriate instruments and qualified review before equipment is built or energized.
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Voltage Divider CalculatorCalculate unloaded and loaded output voltage, divider current and output resistance.Battery Series & Parallel CalculatorEstimate nominal voltage, amp-hours, watt-hours and total cells for an S/P bank.Series & Parallel Resistance CalculatorCombine up to two hundred positive resistor values in series or parallel.LED Resistor CalculatorEstimate a series resistor and its dissipation from supply, forward voltage and current.Capacitor Energy CalculatorCalculate ideal stored energy, charge and farad value from capacitance in microfarads and voltage.AC RMS and Peak CalculatorConvert peak magnitude to RMS, peak-to-peak and crest factor for three ideal waveforms.CCTV Storage CalculatorEstimate decimal video storage from camera count, average bitrate, recording hours, retention days and reserve.