How do I calculate the electrical load for a commercial kitchen?
Add up every appliance's power draw. For each unit multiply amps by volts (and by 1.732 for three-phase) to get VA, sum them for total connected load, then divide by your service voltage to get amps. Add headroom and round up to a standard main-breaker size. This tool does that math; a licensed electrician then applies NEC demand factors to size the actual service.
Does commercial kitchen equipment need 208V or 240V, three-phase?
Much of it does. Cooking equipment, dish machines and booster heaters commonly run on 208V or 240V, and larger units are three-phase. Refrigeration and small wares are often 120V single-phase. Match each unit's nameplate to the building's service before you buy.
What size electrical service does a restaurant need?
It depends entirely on the equipment. A small cafe might run on 100-200A single-phase; a full cooking line with electric ovens, fryers and a high-temp dish machine can need 400-800A three-phase. Total your connected load (this calculator estimates it) and have an electrician size the service with demand factors.
Is this an accurate service size?
It's a planning estimate of connected load. The real service size uses NEC demand factors, simultaneity, motor and continuous-load rules, and voltage drop — all of which a licensed electrician applies. Use this to budget and sanity-check, not to pull a permit.