12-inch ruler

12-inch ruler measures 305.0mm × 30.0mm × 3.0mm. It weighs about 30.0g.

Dimensions

Length305.0 mm
Width30.0 mm
Height3.0 mm
Weight30.0 g

12″ ruler

A standard 12 inch ruler measures 12 inches (30.5 cm) long and 1 to 1.5 inches (2.5 to 3.8 cm) wide, marked in inches and centimeters along its length. This page covers the exact dimensions, common markings, and how a 12 inch ruler compares to a tape measure.

Dimensions

Measurement Inches Centimeters
Length 12.0 30.5
Width 1.0 to 1.5 2.5 to 3.8
Thickness 0.06 to 0.1 1.5 to 2.5

Markings and precision

Most 12 inch rulers mark increments down to 1/16 inch on the imperial side and 1 millimeter on the metric side, allowing for reasonably precise measurements of small objects and drawing straight lines.

Ruler size comparison

Type Length (in) Common use
6 inch ruler 6 Compact, pencil case
12 inch ruler 12 Desk, school use
Yardstick 36 Long, straight-edge tasks

A 12 inch ruler is the most common size for school and office use, long enough to measure most paper sizes while remaining short enough to fit easily in a desk drawer or pencil case.

12 inch ruler vs tape measure

Tool Max length Rigidity
12 inch ruler 1 ft Rigid
Tape measure 16 to 25 ft Flexible, retractable

A ruler’s rigid construction makes it more accurate for short, precise measurements and straight-edge drawing, while a tape measure’s flexibility and length make it better suited for measuring rooms, furniture, and other large objects.

Frequently asked questions

How long is a standard ruler?

12 inches (30.5 cm), the most common length for school and office rulers.

How wide is a 12 inch ruler?

Typically 1 to 1.5 inches (2.5 to 3.8 cm), though width varies by manufacturer and material.

How precise are the markings on a ruler?

Most rulers mark down to 1/16 inch on the imperial scale and 1 millimeter on the metric scale.

What is the difference between a ruler and a yardstick?

A yardstick is 36 inches long, three times the length of a standard 12 inch ruler, and is used for longer straight-edge measurements.

Can a 12 inch ruler measure both inches and centimeters?

Yes. Most 12 inch rulers include both imperial (inch) and metric (centimeter) markings, typically on opposite edges.

Similar in Size

Frequently Asked Questions

How long is a 12-inch ruler?

A 12-inch ruler is 305.0mm (30.5cm) long.

How tall is a 12-inch ruler?

A 12-inch ruler is 3.0mm (0.3cm) tall.

How much does a 12-inch ruler weigh?

A 12-inch ruler weighs about 30.0g.