Free online science and maths tools

Breaks a number into primes with the steps shown.

Converts emissions or energy figures into everyday equivalents like miles driven.

Finds F-distribution probabilities and critical values.

Computes areas and volumes of triangles, circles and cylinders and converts mass, temperature and volume.

Interactive chart of nuclides with decay modes and nuclear structure data.

Browse earthquake locations on a map with depth and time filters.

Interactive 3D walk-through of how a four-stroke engine turns fuel into motion.

Draws chemical structures in the browser and exports them as SMILES or molfile.

Shows AND, OR, NOT, NAND, NOR and XOR gate outputs as you toggle inputs.

Finds roots of a polynomial and shows the work.

Solves systems of linear equations by several methods.

Interactive article with 3D models that show how the parts of a mechanical watch work.

Calculates logP, polar surface area and rule-of-five values for a drawn molecule.

Browser simulations of atoms, molecules and materials for chemistry and physics teaching.

Search atomic energy levels for elements and ions.

Search spectral lines of elements and ions by wavelength.

Look up atomic weights and isotope abundances for all elements.

Look up ionization energies of atoms and ions.

Calculates photon attenuation cross sections for elements, compounds and mixtures.

Runs air parcel trajectory and dispersion models on NOAA servers.

Interactive normal curve showing probabilities, z-scores and percentiles.

Finds cumulative probabilities and values for a normal distribution.

Evaluates definite integrals between two limits.

Computes matrix operations such as inverse and determinant.