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Engineering Calculators, Charts & Reference Tools

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Popular: Voltage drop Wire ampacity Beam calculator Tap drill chart
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Electrical Voltage Drop Calculator Estimate conductor voltage loss from current, length, material, and circuit inputs. Open calculator Structural Beam Calculator Evaluate beam reactions, shear, bending moment, and deflection for common cases. Open calculator HVAC HVAC Load Calculator Estimate heating and cooling requirements from space and envelope inputs. Open calculator Fluids Pipe Flow Calculator Relate pipe geometry, velocity, and flow rate using common unit systems. Open calculator Electrical Three Phase Power Calculator Calculate three-phase power, current, voltage, and power-factor relationships. Open calculator Construction Concrete Mix Calculator Estimate concrete ingredients and quantities from volume and mix inputs. Open calculator HVAC Psychrometric Calculator Calculate common moist-air properties from selected atmospheric conditions. Open calculator Structural Shear & Moment Diagram Calculator Build beam shear and bending-moment diagrams for supported load cases. Open calculator

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Electrical reference Wire Ampacity Chart Compare conductor sizes and ampacity-related reference values. Machining reference Tap Drill Chart Find common tap-drill sizes across supported thread systems. Piping reference Pipe Size Chart Compare nominal pipe sizes with dimensional reference data. Structural reference Floor Joist Span Chart Review joist-span reference data by key framing variables. HVAC reference Refrigerant P–T Chart Look up pressure-temperature relationships for supported refrigerants. Electrical reference NEMA Plug Chart Identify common plug and receptacle configurations by rating.

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Engineering equations, explained

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V = IR Ohm’s Law Voltage · Current · Resistance P + ½ρv² + ρgh = C Bernoulli’s Equation Pressure · Velocity · Elevation δ = 5wL⁴ / 384EI Beam Deflection Load · Span · Stiffness PV = nRT Ideal Gas Law Pressure · Volume · Temperature

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Engineering guides & career resources

Explore practical introductions to the profession, core disciplines, and engineering exam preparation.

Exam preparation FE Civil Exam Guide Review exam topics, preparation considerations, and study resources. Explore the guide Career guide What Do Civil Engineers Do? Understand common roles, project types, and areas of practice. Read the guide Career guide What Do Mechanical Engineers Do? Explore the systems, products, and industries mechanical engineers work on. Read the guide Career guide What Do Electrical Engineers Do? Learn how electrical engineers contribute across power, electronics, controls, and communications. Read the guide

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Technical-use note: Verify assumptions, current codes and standards, manufacturer data, and project requirements before using any result for design, procurement, installation, or field work.

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