These are separate sites, each one a reference for a different trade. Like AmpSizer, they run in your browser with no account. Each description is the site's own.
- SpanRefPublished lumber span tables for floor joists, ceiling joists, rafters and decks, with instant span lookup, a deck calculator and reverse sizing.
- ThreadRefThread and fastener reference for 228+ sizes: metric, Unified and pipe threads with tap drills, clearance holes, torque estimates and wrench sizes.
- GaugePassFree weld symbol, filler metal, discontinuity and welding math reference, plus practice questions and a gauge trainer for welding inspectors.
- 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.
- SidewallRefTire size decoder: break a size like 225/65R17 into overall diameter, sidewall height, circumference and revolutions.
- 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 wire size calculator, the reference tables and the guides are where most visitors start.