Free online science and maths tools

Converts wind speed between knots, mph, km/h and m/s.

Collection of interactive physics simulations covering kinematics, forces, waves and optics.

Calculates cardiac output from heart rate and stroke volume.

Computes the equilibrium potential of an ion from its concentrations on each side of a membrane.

Draw a structure and search PubChem for matching compounds.

Aligns two protein 3D structures and reports RMSD.

View protein structures from the Protein Data Bank in 3D.

Decodes resistor color bands into value and tolerance, and the reverse.

Interactive t curve with p-values and critical values.

Predicts drug-likeness and ADME properties for molecules entered as SMILES.

Computes the Laplace transform and inverse of a function.

Gives t probabilities and critical values for chosen degrees of freedom.

Search catalog of earthquakes by place, time and magnitude.

Simulates ESP32, Arduino, Raspberry Pi Pico and STM32 boards with sensors, displays and WiFi in the browser.

Starts an Arduino Uno project that runs sketches against virtual LEDs, buttons and sensors.

Starts an ESP32-C3 RISC-V project that runs firmware against simulated components.

Starts a MicroPython ESP32 project that runs Python scripts against simulated hardware.

Starts a Raspberry Pi Pico project for simulating C or MicroPython code with virtual parts.

Zoomable 3D map of nearby stars in the Milky Way.

Calculates frequency, duty cycle and component values for a 555 timer astable circuit.

Fits dose-response data to get an EC50 value and curve.

Fits dose-response data to get an IC50 value and curve.

Rotates a shape around a chosen point and shows the new coordinates.

Plots a 3D surface from an equation z equals f of x and y that you type.