Basil — Online Slide Rule

Basil is a free virtual slide rule that runs in your browser: a 3D slide rule simulator you slide and read like the real thing, and a classic 2D view that shows how its logarithmic scales work.

Type a calculation and step-by-step lessons show how to use a slide rule to multiply, divide, square, take roots, logarithms and trigonometry on the C/D, CI, folded (CF/DF), A/K, L and S/T scales.

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