Measuring Obtuse Angles (90° to 180°)
Learn how to identify and measure obtuse angles between 90 and 180 degrees accurately using an online digital protractor.
Target Angle
135°
Angle Type
Obtuse Angle (135°)
Complementary
N/A (Exceeds 90°)
Supplementary
45°
How to Measure This Angle on an Image or Photo
An obtuse angle is greater than 90° but less than 180°. Common examples include bay window wall angles (135°) and octagon corner joints. Position vertex B at the corner intersection to measure wide angles easily.
Visual Diagram: 135° Angle Illustration
Step-by-Step Measurement Procedure
- Upload your image: Drag and drop a photo or blueprint onto the Online Protractor canvas.
- Position Point B (Vertex): Drag the central vertex dot directly onto the corner or angle origin.
- Align Ray A (Baseline): Drag the left handle so ray A aligns perfectly with your reference line.
- Adjust Ray C (Angle Ray): Drag the right handle until ray C lies exactly along the sloped edge.
- Read Angle Output: The tool displays degrees, radians, complementary, and supplementary angles in real time.
Measure Your Angle Now
Upload any photo or image to measure angles with sub-degree accuracy in your browser.
Open Online Protractor Tool