Ruler Plus

This highly accurate ruler allows you to measure various geometric properties of common 2D shapes, including length, perimeter, area, width, height, radius, angles, and circumference. Simply place a small object on your device's screen, and with a few intuitive taps, you can determine its area, perimeter, and other properties.

How It Works

Navigate through the app using the arrow buttons at the top ('<' or '>'). The first two pages enable you to measure an object's dimensions, such as length, width, and height, or the angles between its sides. The following pages are tailored for specific geometric shapes, including squares, rectangles, circles, ellipses, triangles, and circular rings. Use the bottom-right button to switch between displayed characteristics (e.g., area and perimeter, or radius and circumference). Tap the question mark icon to view the mathematical formulas used for calculations.

Measurement Modes

The app offers two methods for precise measurements: Cursor Mode and Automatic Mode.
Cursor Mode: Manually adjust the cursors to perfectly align the object's edges or to fit a regular object within the screen's red measurement area.
Automatic Mode: If an object's edges obstruct manual cursor movement, activate automatic mode using the 'oo' button. The selected cursor(s) will flash and now you are allowed to choose the incremental change (e.g., 0.1, 0.5, 1, 5, or 10 millimeters if the metric system is used). Adjust the cursor using the '+' and '-' buttons until the object is properly aligned within the red zone, then read its area or perimeter.
In case of 3D objects, you can repeat these steps for each surface to determine global parameters such as total surface area or volume.

Note 1: For more accurate results, view the screen perpendicularly and increase screen brightness.
Note 2: If the cursors can move in any direction, the +/- buttons will no longer move them individually. In this case, they will scale up or down the entire figure.
Note 3: Once a cursor is tapped, you can continue to move it even if your finger leaves the working area (but remains in contact with the touchscreen). This feature is useful if the objects are small or easy to displace if touched.

Key Features

- Supports both metric (cm) and imperial (inches) units.
- Option to display lengths in fractional or decimal inches.
- Adjustable step sizes in automatic mode.
- Fine-tuning slider for fast adjustments.
- Two independent cursors with multi-touch support.
- Show formulas used for each geometric shape.
- No ads, no permissions required, easy to use.
- Optional speech output (set phone's speech engine to English).