PopularAvailable
Voltage Drop Calculator
Calculate voltage drop in single-phase, three-phase, and DC cables with interactive real-time visual simulation. Check BS 7671 (UK) or IEC 60364 (international) limit sets.
BS 7671 · UKIEC 60364 · Intl
ELECTRASIM ELECTRICAL TOOLBOX
Interactive Electrical Calculators & Tools
Professional-grade electrical calculators designed for electricians, apprentices, engineers, and students. Visualise current flow, voltage drop, and conductor physics interactively right in your browser.
InteractiveAvailable
Cable Size Calculator
Pick a load, set the run and a voltage-drop limit, and see the smallest cable size (mm²) that keeps the voltage drop inside it — with a live source → cable → load scene that redraws the cable as you change it.
Coming Soon
Power Calculator (kW / kVA / Amps)
Convert and calculate Real Power (kW), Apparent Power (kVA), Reactive Power (kVAR), and full-load current across AC and DC systems.
Coming Soon
Electrical Load Calculator
Estimate maximum demand, apply diversity factors, and calculate total circuit loading for domestic and commercial installations.
Coming Soon
Energy Cost Calculator
Calculate appliance energy consumption, running costs per hour/day/year, and potential savings based on electricity unit rates.
Why Electrical Professionals Choose ElectraSim
Real-Time Interactive Physics
Don't just look at dry numbers. See voltage loss along the cable, observe particle velocity proportional to current, and watch conductor heating in real time.
100% Client-Side Privacy
Calculations execute locally in your browser. No sign-up, no login required, and no confidential project data leaves your device.
Standards & Regulations
Pre-configured with UK BS 7671 Amendment 4 limits (3% lighting, 5% general circuits), IEC standards, and customizable temperature correction.
Mobile On-Site Ready
Fully optimized for on-site calculations on your phone or tablet with full touch support and collapsible tool panels.
Want to build and test complete wiring circuits?
ElectraSim includes a complete interactive wiring laboratory. Wire consumer units, RCBOs, multi-way lighting, sockets, and simulate realistic electrical faults safely.