Reference family
Wire
AWG sizes, ampacity charts, and common branch-circuit lookups for the home workshop. Find the gauge, then a product that matches that size.
Start here
Circuit question or cord run? Start with a chart, a decide page, or the AWG tool.
AWG / ampacity tool
Pick a scene or AWG. Get diameter notes and a restrained product match.
Open tool →
Extension cord gauge
Load + length → suggested cord AWG class for temporary shop power.
Open tool →
What gauge for 20 amp
Short decide page: common copper association for a 20A-style question.
Open page →Browse by topic
Published wire charts and tools — new pages appear here when registered in the content catalog.
Highest-intent decide
What gauge for 20 amp?
Common copper branch-circuit association for a frequent shop question — conditions apply.
Wire gauge chart
AWG to approximate copper diameter in inches and millimeters.
Wire ampacity chart
Simplified current associations next to common AWG sizes.
AWG / ampacity tool
Pick a gauge or a common circuit question — get AWG and a restrained product match.
Wire color code chart
Reference table for NEC US, IEC international, HVAC thermostat, and automotive 12V wire colors.
Extension cord gauge chart
Ampacity and voltage drop for 18-10 AWG extension cords at 25, 50 and 100 ft.
Extension cords
Load + cord length → suggested AWG class for temporary shop power (informational).
How it works
Look up the label, confirm conditions, then a restrained product match.
- 1
State the question
Amps, scene, or cord length — not whole-house design.
- 2
Read the AWG label
From the AWG tool or extension-cord helper — conditions matter.
- 3
Shop a matching product
Restrained SKUs only; confirm AWG on the listing.
FAQ
Disclaimer → Stay safe
Code · listing · conditions
Is this a substitute for the electrical code?
No. Workshop Ref gives common shop associations for education. Always follow local code, listing, temperature ratings, and a qualified electrician when required.
What is AWG?
American Wire Gauge — larger numbers are thinner wire. Diameter and ampacity notes on this site are simplified for workshop reference.
Can I use the extension cord tool for permanent wiring?
No. It is only for temporary cord-style questions. Permanent branch circuits need proper design and inspection.
Other references
Cross-family links for the rest of the shop.
