electrical
Electrical wiring
Calculate cable length, outlets, switches, and conduits for room wiring.
Results are approximate. Verify with manufacturer specifications or consult a professional.
Project inputs
IMPERIAL
Enter a value in ft.
Enter a value in ft.
Enter a value in Your units.
Enter a value in Your units.
Enter a value in Your units.
Includes breakage, spillage, onsite adjustments
Material output
Updates instantly as you type.
Primary output
369.6ft
369.6 ft
≈ 330 ft primary output
Sockets
Your units
10 ea
Switches
Your units
5 ea
Conduits
Your units
38 ea
Results are approximate. Verify with manufacturer specifications or consult a professional.
How it works
Frequently asked questions
Country defaults
United States · USD · imperial
Waste factor: 12.0%
Context & guidance
Results are approximate. Verify with manufacturer specifications or consult a professional.
About This Calculator
Estimate electrical materials needed for residential or commercial wiring projects. Accounts for room dimensions, number of circuits, outlet and switch requirements, wire gauge, conduit needs, and country-specific electrical codes. This calculator provides material estimates for planning purposes. Always consult a licensed electrician for actual installation.
Step-by-Step Instructions
Measure Room Dimensions
Measure room length, width, and height. For multiple rooms, measure each separately. Standard residential rooms are 3-5m (10-16ft) wide, 4-6m (13-20ft) long, and 2.4-2.7m (8-9ft) high. Record all measurements consistently.
Determine Circuit Requirements
Standard residential: 1 circuit per 20 m² (215 ft²) for general lighting/outlets. Kitchens and bathrooms typically need dedicated circuits. Count number of circuits needed based on room size and usage.
Calculate Outlet and Switch Count
Building codes specify minimum outlets: typically 1 outlet per 3-4m (10-12ft) of wall. Count outlets and switches needed. Standard room: 4-8 outlets, 2-4 switches. Kitchens and bathrooms need more.
Estimate Wire Length
Wire length depends on circuit routing, outlet locations, and panel distance. Rough estimate: 1.5-2× room perimeter for basic circuits. Add 20-30% for complex routing, multiple floors, or long panel distances.
Account for Waste Factor
Electrical work typically needs 10-15% waste for cuts, routing variations, and code compliance adjustments. Complex layouts or multi-story buildings may need 15-20% waste.
Calculate Materials
The calculator estimates: wire length (by gauge), number of outlets/switches, junction boxes, conduit (if required), and circuit breakers. Always round up to standard package sizes. Order 10-15% extra for future repairs.
Common Mistakes
Not accounting for local electrical codes
Electrical codes vary by country and region. Minimum outlet spacing, wire gauge requirements, and circuit capacity differ. Always verify local codes before calculating. This calculator provides estimates only—consult a licensed electrician.
Underestimating wire length
Wire routing is rarely straight. Account for vertical runs (to ceiling/attic), horizontal runs (around obstacles), and code-required routing paths. Add 20-30% to straight-line estimates for realistic totals.
Forgetting junction boxes and conduit
Junction boxes are required at every connection point. Conduit may be required by code in some regions or for exposed wiring. Calculate these separately based on routing and code requirements.
Not ordering extra for future repairs
Always order 10-15% extra wire and materials. Electrical work often needs adjustments during installation, and you'll need matching materials for future repairs or expansions.
Pro Tips
Always consult a licensed electrician for actual installation. This calculator provides planning estimates only. Electrical work must comply with local codes and safety standards.
Verify local electrical codes before calculating. Minimum outlet spacing, wire gauge requirements, and circuit capacity vary by country and region.
Plan circuit routing before calculating. Straight runs use less wire than complex routing around obstacles. Consider vertical runs (to ceiling/attic) and horizontal runs separately.
Calculate junction boxes separately: typically 1 per outlet/switch, plus additional boxes for splices and code-required access points.
For conduit, calculate based on routing length plus 10% for fittings and bends. Conduit size depends on wire gauge and number of conductors.
Keep 10-15% extra materials for future repairs and code compliance adjustments. Store in a dry location to prevent damage.
Frequently Asked Questions
Related Calculators
Related Calculators
Flooring & planks
Find total area and required packs for laminate, vinyl, or hardwood.
OpenRoof bundles
Slope-adjusted roof area and bundle counts with ventilation waste.
OpenDrywall sheets
Wall area plus waste divided by preferred sheet size.
OpenInsulation
Calculate insulation volume and rolls for walls, roofs, or floors.
Open