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Slope Calculator

Find the slope of a line between two points.

Pythagorean Theorem Calculator

Find the missing side of a right triangle.

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Sales Tax Calculator

Calculate sales tax and the final price of a purchase.

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Significant Figures Calculator

Round a number to a chosen number of significant figures.

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Pregnancy Due Date Calculator

Estimate a pregnancy due date and gestational age.

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Moon Phase

See the moon phase for any date.

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Day of the Year

See which day of the year a date falls on.

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