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Accurately measure angles on images and screens. Ideal for design, drafting, and geometry. Instantly displays the angle in degrees.
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Image (Supported formats: .bmp, .gif, .jpeg, .jpg, .png, .webp)
Max 20 MB
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When you need to measure precise angles in design blueprints, photos, or screen elements but don't have a physical protractor, this tool automatically calculates and displays the angle using a 3-point method (the vertex plus one point on each side). An angle is the spatial measure formed by two rays starting from the same vertex, measured in degrees (°). This tool provides accuracy down to one decimal place.
How can I improve measurement accuracy?
Zoom in on the image before measuring to ensure all three points are placed exactly in the center of the lines.
Can it measure angles greater than 180°? This tool uses a 3-point method and can measure any angle between 0° and 360°. Just ensure you click the points in the correct order (Vertex → Side 1 → Side 2).
When measuring blurry images, we recommend sharpening them first. Avoid scrolling the page during screen measurement. Measurement results are for reference only; we advise double-checking critical data.
For architectural drafting, we recommend first measuring a reference right angle (90°) to verify tool accuracy. Typical measurement example:
Input: Wall corner vertex in a CAD drawing + one point on each wall line.
Output: 89.3° (indicating a slight deviation).
