मुफ़्त ऑनलाइन टूल

Calculate gear ratio, output RPM, and torque multiplier for spur gear trains. Single-stage, compound 2-stage, RPM solver, and tooth-count finder for target ratios. Enter driver and driven tooth counts — get speed reduction and ideal torque gain. Free, browser-based.

Calculate bolt tightening torque, clamp preload, and nut factor K. Modes: torque from preload (T = KDF), preload from torque, recommended torque from proof load and bolt grade, and nut-factor solver. Metric (mm, kN, N·m) and imperial (in, lbf, lbf·ft) with M6–M24 and Grade 5/8 presets. 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.

Combine and propagate measurement uncertainty with root-sum-of-squares (RSS). Add, subtract, multiply, or divide values with ± uncertainties, convert percent uncertainty, and compute expanded uncertainty U = k·u. 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.

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.

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.