Moon Phase Calendar
Pick a date to see the moon's phase and how much of it is illuminated.
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Light RefractionAdjust the angle and refractive indices to see how light bends passing between two materials.
Concrete Strength EstimatorEstimate compressive strength from a mix ratio and see how it develops as it cures.
Sequence ConvergenceWatch classic sequences like (1+1/n)ⁿ converge toward their famous limits.
Complex Number PlaneMultiply two complex numbers and see how their magnitudes multiply and angles add on the plane.