免費線上工具

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 linear, area, and volume thermal expansion from temperature change. ΔL = αL₀ΔT, ΔA = 2αA₀ΔT, ΔV = 3αV₀ΔT. Bimaterial gap mode for differential expansion between two materials. Material presets for steel, aluminum, concrete, and copper. 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.

Convert numbers to and from scientific notation, e-notation, and engineering notation. Enter decimals (299792458), e-notation (1.23e-5), or 1.23 × 10^5 format. Get normalized scientific, Unicode superscript, engineering (×10³), and decimal forms. Adjustable significant figures. 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.

Prepare analytical standard solutions from solid or stock. Calculate mass to weigh, stock aliquot for dilution (C₁V₁=C₂V₂), and verify actual molarity. Step-by-step lab procedure for volumetric flasks. Free, browser-based.

Plan lab dilutions with pipette volumes, 1:N ratio dilutions, and serial dilution schemes. Get C₁V₁=C₂V₂ stock aliquots, sample and diluent volumes, and step-by-step bench procedures in µL, mL, or L. Free, 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.

Calculate sample size for surveys, mean estimates, A/B tests, and two-group comparisons. Set confidence level, power, margin of error, and effect size. Step-by-step formulas. Free, browser-based.

Countdown and stopwatch timer for lab work. Presets for 1, 5, 10, 15, 30, and 60 minute incubations. Lap times, audio alert on completion. Free, runs in your browser.

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.