PowerAvailable
Power Calculator
Calculate electrical power, current, or voltage with automatic engineering-unit conversion.
Calculator category
Power Calculators
Power calculators support early-stage power electronics design, regulator selection, converter sizing, and thermal troubleshooting. They help hardware engineers estimate dissipation, duty cycle, ripple-related values, and component stress before committing to schematic and PCB design decisions.
Available Calculators
10
Engineering Applications
4
Calculators
Each listed tool links to a working calculator with engineering inputs, formulas, examples, notes, and related resources.
PowerAvailable
Power Factor Calculator
Calculate AC real, reactive, and apparent power with power factor and phase angle.
PowerAvailable
Inrush Current Calculator
Calculate peak startup current, required limiting resistance, and capacitor charge time.
PowerAvailable
Fuse Size Calculator
Estimate minimum and standard fuse ratings from load current, safety margin, and inrush.
PowerAvailable
Voltage Drop Calculator
Estimate wire resistance, voltage drop, load voltage, and cable power loss.
PowerAvailable
Voltage Current Resistance Calculator
Calculate voltage, current, resistance, and power relationships for power-stage and supply calculations.
PowerAvailable
Power Supply Current Calculator
Calculate input current, output current, and recommended supply rating with safety margin.
PowerAvailable
Power Dissipation Calculator
Calculate watt loss from V/I/R combinations and check component rating and derating margin.
PowerAvailable
Efficiency Calculator
Calculate efficiency, input power, output power, loss, and performance status.
PowerAvailable
Battery Capacity Runtime Calculator
Estimate simple runtime, required capacity, or allowable load current with unit conversion.
How to Use These Calculators
Start From the Engineering Question
Choose the calculator that matches the decision you need to make: decode a component marking, size a value, check a frequency response, estimate loss, or verify a safety margin. A category page is useful only when it helps you reach a working tool, so this page lists released calculators only.
Check Units and Assumptions
Calculator results depend on unit choices, idealized formulas, tolerance, temperature, frequency range, and component limitations. Review the formula and engineering notes on each calculator page before using the result in a schematic, BOM, or PCB layout.
Validate Against Real Parts
Use the calculated value as a design reference, then confirm it against datasheets, derating curves, layout parasitics, measurement conditions, and manufacturer limits. The related guides below provide background when a calculation needs more context.
Engineering Applications
Linear Regulators
Buck Converter
Boost Converter
Thermal Design
Related Engineering Guides
Engineering Guide
Understanding Electrical Power
Learn the fundamentals of electrical power, including voltage, current, resistance, watts, energy, Ohm's law, DC and AC power, efficiency, power dissipation, and practical calculations.
18 min · Beginner
Engineering Guide
Power Dissipation and Component Power Ratings
Learn how to calculate power dissipation and choose safe component power ratings for resistors, diodes, BJTs, MOSFETs, regulators, PCB traces, and power supplies using thermal limits, derating, and real operating conditions.
20 min · Intermediate
Engineering Blog
10 Common Engineering Unit Conversion Mistakes (and How to Avoid Them)
Avoid common engineering unit conversion mistakes involving SI prefixes, milli vs mega, micro vs nano, frequency and period, watts vs watt-hours, PCB mils, temperature, significant figures, and calculator inputs.
24 min · Intermediate
Engineering Blog
10 Common PCB Power & Trace Design Mistakes (and How to Avoid Them)
Avoid common PCB power and trace design mistakes including undersized traces, voltage drop, via bottlenecks, RMS-current errors, thermal issues, poor copper pours, and high-current layout problems.
24 min · Intermediate
Engineering Blog
10 Common Power Design Mistakes (and How to Avoid Them)
Avoid common power design mistakes involving watts versus watt-hours, unit prefixes, RMS current, power factor, efficiency, derating, thermal design, startup current, voltage drop, and undersized components.
17 min · Intermediate
Related categories
MOSFETs
MOSFET calculators for switching loss, conduction loss, gate drive, thermal checks, and power hardware design.
Open →Inductors
Inductor calculators for converter design, LC resonance, EMI filtering, RF circuits, and stored energy.
Open →Capacitors
Capacitor calculators for RC timing, filtering, signal coupling, energy storage, and component selection.
Open →