Built-In Electric Wall Oven Breaker & Wire Size
Free online tool • 2026 NEC Compliant
Built-in electric wall ovens are wired separately from a cooktop and typically draw less current than a full electric range. Most single wall ovens require a 20 amp to 30 amp double-pole 240V circuit, while double wall ovens — which house two heating elements — often require 30 amp to 40 amp service. Always check the nameplate rating, since wattage varies significantly by model.
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 nameplate wattage
Find the kW rating on the oven's data plate — single ovens typically run 3.0–5.0 kW.
Calculate current draw
Divide watts by 240V to get amps, then apply the 125% continuous load factor.
Select standard breaker
Round up to the next standard double-pole breaker size: commonly 20A, 25A, or 30A for single ovens.
Select wire size
Match wire to breaker: 20A = 12 AWG, 25A = 10 AWG, 30A = 10 AWG copper.
Frequently Asked Questions
What size breaker does a wall oven need?
Most single built-in electric wall ovens draw 3.0–5.0 kW and require a 20A or 25A double-pole 240V breaker with 12 or 10 AWG copper wire. Double wall ovens draw more and often need a 30A–40A breaker with 10 or 8 AWG copper wire. Check the nameplate for the exact kW rating.
Is a wall oven on the same circuit as the cooktop?
Not typically. Built-in wall ovens and separate cooktops are usually wired as two independent dedicated circuits, each sized to its own nameplate rating, rather than sharing one circuit like a combined range.
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