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Science Calculators

Explore free science calculators for physics, astronomy, and engineering — from escape velocity and time dilation to asteroid impacts and the Drake equation. Curiosity-driven tools backed by real formulas.

25 free science calculators

Ecological Footprint Calculator

Calculate your ecological footprint and find out how many Earths we would need if everyone lived like you. Quick lifestyle quiz using Footprint Network data.

Tree Carbon Offset Calculator

Calculate how many trees you need to offset your carbon emissions. Based on USDA data showing mature trees absorb about 22 kg (48 lbs) of CO2 per year.

Your Weight on Other Planets

Find your weight on the Moon, Mars, Jupiter, and other planets. Enter your Earth weight or mass to see what you weigh using surface gravity for every world.

Nuclear Blast Effects Calculator

Calculate nuclear blast radii for overpressure thresholds. Enter a yield in kilotons to see fireball size and damage zones using cube-root scaling physics.

Asteroid Impact Simulator

Calculate asteroid impact energy, TNT equivalent, and crater size. Enter diameter, density, and velocity to simulate cosmic collisions with simplified physics.

Drake Equation Explorer

Explore the Drake equation to estimate communicative civilizations in our galaxy. Adjust all 7 parameters and see how each factor affects the final estimate.

Age on Other Planets

Find your age in planetary years on Mars, Venus, Jupiter and beyond. Enter your Earth age to see how many birthdays you would have on each planet in the system.

Space Travel Time Calculator

Calculate how long it takes to travel to the Moon, Mars, or other destinations at any speed. Compare walking, driving, rocket, and light-speed times instantly.

Horizon & Earth Curvature Calculator

Calculate the distance to the horizon from any height and see how much of a distant object is hidden by Earth curvature. Learn why ships vanish hull-first.

Day/Night Terminator Calculator

Calculate the position of the day and night terminator line on Earth for a date and time. Find the subsolar point and see which areas are in daylight.

Relativity Time Dilation Calculator

Calculate relativistic time dilation using the Lorentz factor. Enter speed as a fraction of light speed to see how time slows down for fast-moving objects.

Relativistic Doppler Shift Calculator

Doppler shift calculator using the relativistic redshift formula. Enter emitted and observed wavelengths to find the velocity and redshift between two colors.

Escape Velocity Calculator

Calculate escape velocity from any spherical body. Enter mass and radius to find the minimum speed needed to break free of its gravity, or use planet presets.

Dinosaur Speed Estimator

Estimate dinosaur running speed from trackway fossils using Alexander's method. Enter stride length and hip height to calculate how fast dinosaurs moved.

Falling Object Calculator

Calculate terminal velocity, impact speed, and energy for falling objects with air resistance. Test the famous penny-drop myth with real physics for any mass.

Sound Travel Time Calculator

Calculate how long sound takes to travel any distance. Find thunder delay from lightning distance, echo times, and speed of sound in air, water, and steel.

Human Scale Universe Calculator

Scale the solar system to everyday objects. If the Sun was a basketball, where would Earth be? Visualize cosmic distances in terms you can actually picture.

Pendulum Length Calculator

Find a pendulum period from its length, or the length needed for a target period. Enter pendulum length to see swing time, frequency, and beats per minute.

Ruler Drop Reaction Time Calculator

Calculate your reaction time using the classic ruler drop test. Enter the catch distance to find your reflexes in milliseconds, a fun physics experiment to try.

Black Hole Calculator

Calculate the Schwarzschild radius (event horizon) for any mass and see what happens if Earth became a black hole. Explore how black hole size scales with mass.

Flight Carbon Footprint Calculator

Calculate your flight CO2 emissions. Enter the distance and cabin class to see kilograms of carbon dioxide per passenger, based on ICAO emission methodology.

Water Footprint of Food Calculator

Calculate the hidden water cost of your meal. See how many litres of water are needed to produce beef, chicken, rice, and veg using Water Footprint data.

Plastic Waste Calculator

Calculate how much plastic waste you generate per year. Count bottles, bags, and containers to estimate your annual plastic footprint in kilograms and cut it.

Lifetime Trash Calculator

Calculate how much trash you will generate over your lifetime. Based on World Bank waste data averaging 0.79 kg of garbage per person per day across the globe.

Earthquake Energy Calculator

Convert earthquake magnitude to energy in Joules and TNT equivalents. Uses the Gutenberg-Richter relation to show the immense power of seismic events.