Electrical Calculator
Estimate Tier 1 wire footage, boxes, and outlets with an editable slack allowance.
Sum your actual run lengths, keep the slack assumption visible, and use the tally fields for simple box and outlet counts.
Material ListTier 1 wire runs
Enter each branch-circuit run and adjust the visible slack allowance for the job.
Tier 1 boxes and outlets
Simple user-entered tally by type; these counts are not inferred from the run lengths.
Box fill (NEC 314.16(B) formula)
Optional. Enter a box volume and at least one conductor to check required box-fill volume against the box you're using. Skipped when left off.
Wire sizing / voltage drop
Optional. Solves the minimum conductor size for a target voltage-drop budget using standard Ohm's-law-family physics and public AWG resistivity constants. Skipped when left off.
GFCI/AFCI location flags
Optional. Tag devices by location to flag conventional GFCI (kitchen countertop, bathroom, garage, outdoor, unfinished basement/crawlspace) and AFCI (bedroom, NEC 210.12) coverage. General guideline only -- verify locally.
Circuit / breaker grouping
Optional. Suggests circuit groupings so each circuit's summed load stays at or under 80% of the breaker rating. Simple rule of thumb -- verify locally before finalizing panel scheduling.
You'll need 192.5 ft of wire and 0 boxes for this job.
You'll need
Combined wire and box estimate
Warnings
- INFO Advanced code table lookup is not available until reference data is verified.
- INFO This is a general reference only. Verify local requirements and field conditions before installation.
Detail values
Assumptions
- Slack allowance: 10% (editable)
Included: wire footage with slack allowance, box and outlet tally.
Not included: labor, permits, inspection fees, fixtures and fittings beyond what's itemized above.
Formula details
- Wire footage: sum(runLengths) * (1 + slackAllowancePercent / 100)
Tier 2 conduit fill
Advanced code table lookup is not available until reference data is verified.
FAQ
Why is the slack allowance editable?
CrewMeasure starts at 10%, but job conditions such as box drops, splices, and service loops can require a different allowance.
Why is conduit fill unavailable?
Conduit fill needs verified NEC Chapter 9 Table 4 and Table 5 datasets. CrewMeasure does not substitute unverified values.
Disclaimer
This is a general reference and material-estimate tool only. Verify local requirements, equipment specifications, and field conditions before installation.