Construction & DIY
Calculators.

Materials, electrical, roofing, and landscaping — build with confidence, not guesswork.
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Electrical

14 tools

Wire sizing, resistor values, and circuit calculations — get the math right before you wire.

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Wire Size Calculator

NEC-compliant wire gauge for safe, efficient circuits.

gaugeampacity
Ω

Ohm's Law

Voltage, current, resistance, and power relationships.

circuitpower

Voltage Divider

Output voltage from two resistors in series.

resistorsignal
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LED Resistor

Current-limiting resistor for single and series LEDs.

LEDcurrent
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Resistor Color Code

4, 5, and 6-band resistor color code decoder.

color codebands
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Electricity Cost

Monthly and annual energy cost from watts and hours.

costkWh

Generator Sizing

Calculate backup generator size from your appliance list.

generatorwatts
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Circuit Breaker Size

NEC-compliant breaker sizing with GFCI/AFCI requirements.

breakerNEC
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Conduit Fill

Check NEC wire fill percentage for EMT, PVC, and Rigid conduit.

conduitfill%
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Solar Panel Size

How many panels you need, battery sizing, and 25-year ROI.

solarPV

EV Charger Sizing

Breaker size, wire gauge, panel load & charging time per NEC 625.

NEC 625Level 2

Electrical Panel Load

NEC 220 demand load calculation — service size and capacity analysis.

NEC 220demand factor
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Ground Fault (GFCI) Calculator

NEC 2020 GFCI and AFCI requirements by room type — outlet count, code sections, and protection cost estimates.

GFCIAFCINEC 2020
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Lighting Layout Calculator

Foot-candle targets, fixture count, and grid spacing by room type — zonal cavity method with efficacy and energy density checks.

foot-candlesfixture countzonal cavity

Structural & Framing

8 tools

Size beams, frame walls, calculate lumber quantities — professional structural calculations without the engineering fees.

Excavation & Aggregate

3 tools

Calculate gravel, crushed stone, and fill material quantities — tons, cubic yards, truck loads, and cost.

Masonry & Foundation

3 tools

Size footings, calculate concrete volume, and check soil bearing capacity — IRC R403 code references included.

Drywall

4 tools

Calculate drywall sheets, joint compound, tape, and screws — full materials list with GA-214 finish level guide.

Insulation

5 tools

R-value requirements by IECC climate zone — material quantities, thickness, cost, and energy payback.

Interior Finishing

4 tools

Carpet, countertops, molding, and trim — precise quantities so you buy once and waste nothing.

Windows & Doors

5 tools

Energy performance and rough opening sizing — get windows and doors right before framing.

Pool & Water Features

4 tools

Volume, liner sizing, and chemical starting points for pools, ponds, and water features.

Demolition

2 tools

Estimate debris volume, weight, and disposal costs before the sledgehammer swings.