Tutorials
Step-by-step workflows for photos, screenshots, PDFs, and diagrams. Learn alignment, snap, 180°/360° reading, and exporting results.
- Pick your input: photo, screenshot, PDF, CAD, or blueprint.
- Align a baseline first, then choose 180° or 360° mode.
- Export a report or data table when you need to share results.
Featured tutorials
Measure an angle on a photo
Upload or paste an image, align a clear edge, and read the angle with snap and guides.
Measure an angle from a camera photo
Take a straight-on photo, align a baseline with the grid, then measure and export.
How to use an online protractor
A general workflow: upload/paste, align, choose 180°/360°, then export.
Measure the angle between two lines
A clean workflow for diagrams: align the baseline, trace both lines, and read the included angle.
Measure a reflex angle (360°)
Switch to 360° mode, choose interior vs reflex, and avoid reading the wrong scale.
Measure triangle angles (A+B+C=180°)
Measure all three corners and sanity-check the sum before exporting.
Measure an angle in a PDF
Take a screenshot from your PDF, paste it, align, then measure and export.
Measure an angle on a screenshot
Copy/paste a snip, align a baseline, then read and export the angle.
Measure an angle on iPhone
Take a screenshot on iOS, upload it, align, then read and export the angle.
Measure an angle on Android
Screenshot on Android, upload it, align a baseline, then measure and export.
Measure an angle on a CAD drawing
Measure from CAD screenshots or exports with a clean alignment workflow.
Measure an angle on a blueprint
Scan or screenshot a plan, align a reference line, then measure and export.
Measure roof pitch / slope angle
Use a roof photo or plan view, align a horizontal baseline, then read the slope angle.
Roof pitch to degrees (and degrees to pitch)
Convert pitch ratios (x/12) and slope angles using a simple workflow you can verify on an image.
Percent grade to degrees (and vice versa)
Convert percent grade (%) and slope angle (degrees), and relate it to pitch (x/12) for construction use.
Slope ratio (1:n) to degrees (and vice versa)
Convert slope ratios like 1:12 or 1:20 to degrees (and to % grade), and verify the result on a photo or plan.
Measure ramp slope angle
Measure ramp slope in degrees from a photo or plan by aligning a true horizontal baseline.
Measure stair stringer angle
Measure the stair stringer (slope) angle from a photo or plan with a horizontal baseline.
Measure an angle on a video frame
Pause, take a screenshot, paste it, then measure and export.
Angle finder / angle meter workflow
A reliable workflow to land on clean angles and avoid common reading mistakes.
Virtual vs digital protractor (what people mean)
Quick definitions, and which features matter when you measure on real images.