These are separate sites, each one a reference for a different trade. Like SpanRef, they run in your browser with no account. Each description is the site's own.
- AmpSizerWire size, ampacity, voltage drop and conduit fill calculators built on published 2023 NEC tables, from 14 AWG to 2000 kcmil in copper or aluminum.
- ThreadRefThread and fastener reference for 228+ sizes: metric, Unified and pipe threads with tap drills, clearance holes, torque estimates and wrench sizes.
- MixRatioConcrete, mortar and grout calculators for slabs, footings, columns and post holes: cubic yards, cubic metres and bag counts, plus 179 worked examples.
- CogoKitFree COGO calculators for land surveyors: horizontal and vertical curves, traverse closure, area by coordinates and bearings, plus FS exam practice.
- EngiRef119 engineering formulas with solvers, 56 materials, 134 unit conversions, constants and reference tables.
- FittingKeyHydraulic and pneumatic fitting identifier: match thread diameter, threads per inch and seat across 110 sizes and 10 standards.
- IrrigauditRun a catch-can irrigation audit in the browser: distribution uniformity, precipitation rate, cycle-soak programs and a printable client report.
- ReadTheSetLearn to read construction drawings by reading a real set: floor plans, sections, details and schedules, with measuring, callout drills and graded reasoning.
Looking for something on this site instead? The span tables, the span lookup and the guides are where most visitors start.