Speedcert vs Voltbox

SpeedCert helps electricians and contractors create, manage and share UK electrical and safety certificates on iPhone and iPad. Complete EICR, EIC, Minor Works, PAT and many more certificate types with guided workflows, professional PDFs and optional offline access so you can work on site without a reliable signal. Manage clients and installations, capture signatures and photos, and sync across devices when you are back online. Built for UK compliance workflows including BS 7671, with team features and integrations for growing businesses.

Voltbox is a professional calculator toolkit for electricians, built around the NEC (National Electrical Code). Fast, accurate, and yours to own — pay once, keep it forever. 18 CALCULATORS Fundamentals (free) • Ohm's Law — voltage, current, resistance, power, series/parallel • Wire & Cable Sizing — NEC ampacity lookup Dwelling Load • Load Calculation — dwelling feeder/service sizing (NEC 220) • Range Demand — cooking appliance demand load (NEC 220.55) • Generator Sizing • Existing Load Evaluation — headroom check for adding new loads to an existing service Circuit Design • Voltage Drop — for any run length and load • Motor / Transformer Sizing — full-load amps per NEC 430 • Grounding & Bonding — NEC 250.66 / 250.122 • EV Charging — NEC 625 • HVAC Circuit Sizing • Feeder Tap Conductor — NEC 240.21(B) • Spa Bonding Exemption • Branch Circuit Sizing Installation • Conduit Fill — max conductors per conduit size, including bare wire • Box Fill — junction box conductor capacity • Conduit Bending — offset & 90° stub • Light Meter — jobsite illumination check against OSHA/egress/IES minimums WHY VOLTBOX • One-time purchase for Pro — never a subscription, never a recurring fee • Save and organize calculations by project • Built for the job site: fast, no clutter, no login screens, works with no signal • No account required — open the app and start calculating Ohm's Law and Wire Sizing are free. Unlock Pro once to get every other calculator. Voltbox is a reference tool based on the NEC. Always verify results against the current code edition adopted in your area and confirm compliance with a licensed electrician or your local inspector before performing any installation.