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Ohm's Law Calculator

Calculate voltage, current, resistance, or power using Ohm's law (V = I × R) with formula steps.

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Voltage Calculator

Calculate voltage (V) from current and resistance using Ohm's law with detailed formula.

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Current Calculator

Calculate current (I) from voltage and resistance with step-by-step Ohm's law.

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Resistance Calculator

Calculate resistance (R) from voltage and current with Ohm's law formula.

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Power Calculator (P = V × I)

Calculate electrical power from voltage and current with step-by-step formula.

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Resistor Color Code Calculator

Decode resistor values from color bands with 4-band, 5-band, and 6-band support.

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Series & Parallel Resistance

Calculate total resistance for series and parallel resistor circuits.

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Conductance Calculator

Calculate conductance (S) from resistance with detailed formula and units.

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Power Consumption Calculator

Calculate electrical power consumption and cost for appliances and equipment.

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Energy Cost Calculator

Calculate electricity cost based on power consumption, time, and rate per kWh.

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kWh to Joules Converter

Convert kilowatt-hours (kWh) to joules (J) for energy calculations.

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Watt to Horsepower Converter

Convert watts (W) to horsepower (HP) for mechanical power equivalence.

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BTU to kWh Converter

Convert British Thermal Units (BTU) to kilowatt-hours (kWh).

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Appliance Energy Calculator

Calculate annual energy consumption and cost for household appliances.

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LED vs Incandescent Savings

Compare energy savings and cost between LED and incandescent bulbs.

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Appliance Wattage Estimator

Estimate wattage of common household appliances from typical values.

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Voltage Drop Calculator

Calculate voltage drop in electrical circuits with wire size, length, and current.

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AC Voltage Calculator

Calculate AC voltage parameters (peak, RMS, average) for sinusoidal waveforms.

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DC Voltage Calculator

Calculate DC voltage, current, and resistance for DC circuits.

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Current Density Calculator

Calculate current density (A/m²) in conductors with cross-sectional area.

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RMS to Peak Converter

Convert RMS voltage to peak voltage and vice versa for AC signals.

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Line-to-Line Voltage Calculator

Calculate line-to-line voltage from phase voltage in three-phase systems.

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Phase Voltage Calculator

Calculate phase voltage from line-to-line voltage in three-phase systems.

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Voltage Divider Calculator

Calculate output voltage for resistor divider circuits with step-by-step formula.

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Resistor Color Code Calculator

Identify resistor values from color bands (4-band, 5-band, 6-band) with tolerance.

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Series Resistance Calculator

Calculate total resistance for resistors connected in series with details.

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Parallel Resistance Calculator

Calculate total resistance for resistors connected in parallel with formula.

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Conductivity Calculator

Calculate electrical conductivity (σ) from resistance and dimensions.

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Resistivity Calculator

Calculate material resistivity (ρ) from resistance, length, and area.

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Temperature Coefficient Calculator

Calculate resistance change with temperature using temperature coefficient.

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SMD Resistor Code Calculator

Decode SMD resistor values from 3-digit, 4-digit, and EIA-96 codes.

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Light Dependent Resistor (LDR) Calc

Calculate resistance change for LDR based on light intensity.

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Wire Size Calculator

Calculate minimum wire size (AWG) based on current, voltage, and distance.

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AWG to mm² Converter

Convert American Wire Gauge (AWG) to square millimeters (mm²) and vice versa.

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Voltage Drop Calculator

Calculate voltage drop for wire runs with NEC code compliance.

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Wire Resistance Calculator

Calculate wire resistance based on material, length, and gauge.

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Wire Ampacity Calculator

Calculate current-carrying capacity (ampacity) of wires based on NEC tables.

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Cable Sizing Calculator

Calculate cable size for electrical installations with current and distance.

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Busbar Current Calculator

Calculate current-carrying capacity of copper or aluminum busbars.

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Wire Weight Calculator

Calculate wire weight based on material, gauge, and length.

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RC Time Constant Calculator

Calculate RC time constant (τ = R × C) for resistor-capacitor circuits.

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RL Time Constant Calculator

Calculate RL time constant (τ = L / R) for resistor-inductor circuits.

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LC Resonant Frequency Calculator

Calculate LC resonant frequency for inductor-capacitor circuits.

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Power Factor Calculator

Calculate power factor, apparent power, real power, and reactive power.

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Impedance Calculator

Calculate impedance for series and parallel RLC circuits.

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Capacitance Calculator

Calculate capacitance (C) from charge and voltage or plate dimensions.

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Inductance Calculator

Calculate inductance (L) from voltage, current, and time or coil dimensions.

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Series vs Parallel Circuit Calculator

Compare series and parallel circuits with total resistance and power calculations.

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Motor Power Calculator

Calculate motor power (HP) from voltage, current, efficiency, and power factor.

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Motor Torque Calculator

Calculate motor torque (lb-ft or N-m) from power and RPM.

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Generator Power Calculator

Calculate generator output power from voltage, current, and power factor.

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Motor Efficiency Calculator

Calculate motor efficiency from input power and output power.

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Motor Starting Current Calculator

Calculate motor inrush current and starting characteristics.

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Motor Speed Calculator

Calculate motor RPM from frequency and number of poles (synchronous speed).

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Generator Fuel Consumption

Calculate generator fuel consumption and runtime based on load and efficiency.

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Motor Sizing Calculator

Size electric motors for pumps, fans, conveyors, and other applications.

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Circuit Breaker Sizing

Calculate circuit breaker size based on load current and NEC standards.

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Fuse Sizing Calculator

Calculate fuse rating based on load current and type of application.

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Short Circuit Current Calculator

Calculate available short-circuit current in electrical systems.

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Grounding Electrode Calculator

Calculate grounding electrode resistance for safety systems.

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Lightning Arrester Calculator

Calculate lightning arrester requirements for building protection.

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NEC Load Calculation

Calculate electrical load for residential and commercial buildings per NEC.

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Arc Flash Calculator

Calculate incident energy and arc flash boundary for electrical safety.

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Electrical Safety Compliance

Check compliance with electrical safety standards and requirements.

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What Are Electrical Calculators?

Our Electrical Calculators collection provides essential tools for electricians, electrical engineers, students, and anyone working with electrical systems. Whether you need to calculate Ohm's law, size wires, analyze circuits, estimate energy costs, or ensure safety compliance, these calculators deliver accurate results with clear explanations.

From voltage and current calculations and wire sizing to circuit analysis, motor sizing, and safety compliance, our tools cover the full spectrum of electrical engineering needs.

How to Use This Directory

  • Search: Type a keyword into the search bar to find specific calculators by name or description.
  • Filter by Category: Use the dropdown to narrow down to a specific electrical topic — each option shows the number of calculators available.
  • Click to Use: Each card links directly to the tool. Click on any card to start your electrical calculation instantly.
  • Explore Category Pages: Use the "Explore All Electrical Calculator Categories" section to access dedicated pages with even more tools.

Why Use Our Electrical Calculators?

  • Comprehensive Coverage: Covers Ohm's law, power, energy, voltage, current, resistance, wire sizing, circuit analysis, motors, generators, and safety standards.
  • Accurate & Reliable: Uses industry-standard formulas and NEC code references.
  • Free & Accessible: No registration, no fees — use any tool instantly on any device.
  • Educational: Many tools show formula steps and explain the underlying principles.
  • Professional & DIY Friendly: Designed for both professionals and home enthusiasts.

❓ Electrical Calculators FAQ

What types of electrical calculations can I perform?

You can perform Ohm's law calculations (voltage, current, resistance, power), wire sizing and voltage drop calculations, circuit analysis (RC, RL, LC), power and energy consumption calculations, motor and generator sizing, and safety compliance calculations.

How do I use the Ohm's Law Calculator?

Enter any two values (voltage, current, resistance, or power) and the calculator will compute the remaining values using Ohm's law (V = I × R) and power formulas (P = V × I).

How do I calculate voltage drop?

Use our Voltage Drop Calculator. Enter the current, wire length, wire gauge, and material. The calculator will compute the voltage drop and check compliance with NEC standards.

How do I determine the right wire size?

Use our Wire Size Calculator. Enter the load current, voltage, wire length, and installation conditions. The calculator will recommend the minimum AWG wire size per NEC standards.

How do I calculate electrical energy consumption?

Use our Power Consumption Calculator or Energy Cost Calculator. Enter the appliance wattage and usage time to calculate energy consumption in kWh and estimated cost.

What is the difference between AC and DC circuits?

DC (direct current) flows in one direction with constant voltage. AC (alternating current) reverses direction periodically. Our calculators handle both types with appropriate formulas.

How do I calculate power factor?

Use our Power Factor Calculator. Enter the real power (kW) and apparent power (kVA) or voltage, current, and phase angle to compute the power factor.

How do I size a circuit breaker?

Use our Circuit Breaker Sizing calculator. Enter the load current and application type to determine the correct breaker size based on NEC guidelines.

Are these calculators compliant with NEC standards?

Yes, our calculators reference NEC (National Electrical Code) standards where applicable for wire sizing, voltage drop, circuit breaker sizing, and electrical safety.

How often are new electrical calculators added?

We regularly add new calculators based on user requests and industry needs. If you have a suggestion, please contact us.