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Triangle area calculator

Triangle area = base × perpendicular height ÷ 2.

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Answer

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Triangle area = base × perpendicular height ÷ 2.

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Precision and calculation record
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Step-by-step calculation
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    Formula and assumptions
    Height must meet the base at a right angle. A sloping side is not the height unless it is perpendicular to the base.
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    Updated 
    Using Triangle area calculator
    Triangle area = base × perpendicular height ÷ 2.
    Height must meet the base at a right angle. A sloping side is not the height unless it is perpendicular to the base.
    Next: Triangle calculator
    A worked example
    With base = 8, perpendicular height = 3, the area is 12.
    Next: Right triangle calculator
    Before you use the result
    Height must meet the base at a right angle. A sloping side is not the height unless it is perpendicular to the base.
    Example results for base
    These examples use Perpendicular height: 3. They are reference calculations, not recommended settings.
    BaseArea
    46
    812
    1624
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    ToolOctopus. “Triangle area calculator.” Updated 2026-09-26. https://tooloctopus.com/triangle-area-calculator.
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