Kostenlose Online-Tools
268+ free online tools for PDF, images, SEO, developers, color, and productivity. Fast, browser-based, and private — no signup, no installs, no limits. Search above or browse by category below.
Total tools26810.8K total uses
Categories13Active categories
Most usedJSON Formatter4.1K uses
Recently addedExperiment RandomizerNewest tool
Matrix Calculator
Add, subtract, multiply, transpose, invert, and find determinants of matrices up to 6×6.
Used 1 times•Updated 21 minutes ago
Vector Calculator
Compute 2D and 3D vector operations — add, subtract, dot product, cross product, magnitude, unit vector, angle, and projection — with steps.
Used 1 times•Updated 21 minutes ago
GCD Calculator
Find the greatest common divisor (GCD) and LCM of two or more positive integers with Euclidean algorithm steps and prime-factor method.
Used 1 times•Updated 19 minutes ago
Combinations Calculator
Calculate combinations nCr and permutations nPr with factorial formulas, step-by-step work, and support for large results.
Used 1 times•Updated 19 minutes ago
Standard Deviation Calculator
Calculate sample and population standard deviation and variance from any data set with squared-deviation steps.
Used 1 times•Updated 30 minutes ago
Mean Median Mode Calculator
Find the mean, median, and mode of any data set with frequency tables, sorted data, and step-by-step work.
Used 1 times•Updated 30 minutes ago
Light Year Converter
Convert light-years to parsecs, AU, kilometers, meters, and miles. Enter any astronomical distance and get instant conversions with formulas. Free, browser-based.
Used 1 times•Updated 2 minutes ago
Orbital Period Calculator
Calculate orbital period from altitude or radius using Kepler's third law. Presets for ISS, geostationary orbit, Moon, and Earth around the Sun. Free, browser-based.
Used 1 times•Updated 29 minutes ago
Moon Phase Calculator
Find the moon phase for any date — new moon, full moon, quarters, and crescents. Shows illumination %, moon age, and days to next new or full moon. Free, browser-based.
Used 1 times•Updated 20 minutes ago
Blackbody Radiation Calculator
Calculate blackbody peak wavelength, Stefan–Boltzmann flux, and Planck spectral radiance from temperature. Wien's law and σT⁴. Free, browser-based physics tool.
Used 1 times•Updated 31 minutes ago
Gravity on Other Planets
Compare surface gravity on Mercury, Venus, Mars, Jupiter, the Moon, and every planet. See gravity in m/s², percent of Earth, and weight for any mass. Free, browser-based.
Used 1 times•Updated 20 minutes ago
Heat Index Calculator
Calculate heat index (feels-like temperature) from air temperature and relative humidity. Uses the official NWS Rothfusz formula with heat risk guidance. Free, browser-based.
Used 1 times•Updated 21 minutes ago