Dishwasher Breaker & Wire Size
Free online tool • 2026 NEC Compliant
Most residential dishwashers run on a dedicated 120V circuit protected by a 15 amp or 20 amp breaker, with 14 or 12 AWG copper wire respectively. Since the 2020 NEC, dishwasher branch circuits require GFCI protection under NEC 210.8(D) — a change many older installations do not reflect. High-end or commercial-style dishwashers may draw more current, so always check the nameplate.
Recommended Sizing
NEC Standard SizeBreaker Type: Standard Inverse-Time
NEC Reference Note: 125% multiplier applied for continuous loads per NEC 210.20(A).
How to Use This Calculator
Check dishwasher nameplate amps
Most standard residential dishwashers draw well under 12A; confirm on the nameplate.
Select standard circuit size
Use a 15A circuit (14 AWG) or 20A circuit (12 AWG) dedicated to the dishwasher.
Confirm GFCI protection
Verify the circuit is GFCI protected per NEC 210.8(D) if under 2020 NEC or later.
Verify dedicated circuit
Confirm no other appliances share this circuit.
Frequently Asked Questions
What size breaker does a dishwasher need?
Most residential dishwashers require a dedicated 15A or 20A 120V circuit. 15A circuits use 14 AWG copper wire; 20A circuits use 12 AWG copper wire. Check the nameplate amp rating, especially for larger or commercial-style units.
Does a dishwasher circuit need GFCI protection?
Yes, as of the 2020 NEC. Section 210.8(D) requires GFCI protection for dishwasher branch circuits. This applies to new installations and major renovations under jurisdictions that have adopted the 2020 NEC or later — check your local code adoption cycle.
Can a dishwasher share a circuit with other appliances?
A dedicated circuit is strongly recommended and required in most jurisdictions. Sharing a circuit with a garbage disposal or other kitchen appliance can cause nuisance trips and is discouraged by most dishwasher manufacturers.
Specific Sizing Guides & Calculators
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