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Calculate fluid velocity from volumetric flow rate and cross-section geometry. Modes: circular pipe, rectangular channel, annulus, known area, continuity (pipe reducer), and velocity unit converter. Reynolds number and flow regime. Metric and imperial units. Free, browser-based.

Calculate pump hydraulic power, shaft power, and motor sizing from flow rate and head. Modes: hydraulic power (ρgQH), brake power with pump efficiency, motor input with motor efficiency, and power from pressure rise. Results in kW, hp, and W. Water and custom specific gravity. Metric and imperial units. Free, browser-based.

Calculate maximum beam deflection and bending moment for simply supported, cantilever, and fixed-end beams under center point loads or uniform distributed loads. Enter span, E, I, and load — results in mm or inches with L/360 and L/250 limit checks. Free, browser-based.

Calculate axial, shear, bending, and torsional stress from force, area, moment, and geometry. Compare to yield strength for safety factor. Metric (MPa) and imperial (psi) units. Free, browser-based.

Calculate engineering axial strain, shear strain, Hooke's law strain (σ/E), thermal strain (αΔT), and lateral Poisson strain. Results in dimensionless ε, microstrain (με), and percent. Metric and imperial units. Free, browser-based.

Calculate Young's modulus E = σ/ε from stress and strain, or from a tensile test (force, area, elongation). Convert between GPa, MPa, Msi, ksi, and psi. Compare to common material references. Free, browser-based.

Calculate heat transfer by conduction (Fourier), convection (Newton), radiation (Stefan–Boltzmann), overall U-value, and composite wall assemblies. Enter geometry, temperatures, and material properties — get heat rate in W, kW, and BTU/hr with thermal resistance. Metric and imperial units. Free, browser-based.

Calculate safety factor, margin of safety, and utilization from strength and stress or load and capacity. Modes: SF from stress, SF from load, allowable stress, required strength, and design pass/fail check. Material yield presets. Metric (MPa, kN) and imperial (ksi, lbf). Free, browser-based.

Count significant figures, round to N sig figs, and add, subtract, multiply, or divide with correct precision rules. Enter decimals, trailing zeros, or scientific notation. Free, instant, browser-based.

Calculate percent error, absolute error, relative error, and percent difference between measured and accepted values. Step-by-step formulas for physics and chemistry lab reports. Free, instant, browser-based.

Convert microliters (µL) to milliliters, liters, nanoliters, cubic centimeters, and more. Instant lab volume conversions with all units shown at once. Free, browser-based.

Plan serial dilutions with fold factors, transfer volumes, and concentration at each step. Find how many steps to reach a target, or set up CFU plate-count dilutions. Full table with log₁₀ values and lab procedure. Free, browser-based.