How wide is a standard US stop sign?
A standard US stop sign is about 76 cm (2 ft 6 in) across.
Size source: en.wikipedia.org
Compared with things you know
- About 3.2 times as wide as a basketball (24 cm)
- About 43% of the length of an adult bicycle (1.75 m)
- About 17% of the length of a family car (4.5 m)
Stop sign dimensions
| Measurement | Metric | Imperial | Source |
|---|---|---|---|
| Width (across opposite flats) | 76.2 cm | 30 in | [1][2] |
| Letter height (STOP legend) | 25.4 cm | 10 in | [2] |
| White border width | 1.9 cm19 mm | 0.75 in | [2] |
Standard: MUTCD R1-1 (US Manual on Uniform Traffic Control Devices)
Stop sign sizes[1][2]
| US, single-lane conventional road | 76.2 cm (2 ft 6 in)30 x 30 in |
|---|---|
| US, multi-lane road or expressway | 91.4 cm (3 ft 0 in)36 x 36 in |
| US, oversized | 1.22 m (4 ft 0 in)48 x 48 in |
| Vienna Convention (1968) | 60 cm – 1.2 m (2 ft 0 in – 3 ft 11 in)600, 900 or 1200 mm |
| UK and New Zealand | 75 cm – 1.2 m (2 ft 6 in – 3 ft 11 in)750, 900 or 1200 mm |
| First US stop signs | 61 cm (2 ft 0 in)24 x 24 in, black on white |
How it is measured
A stop sign is a red octagon. In the United States its size is given across opposite flats. The standard sign is 30 in (76 cm) across, with a white STOP legend 10 in (25 cm) tall and a 3/4 in (19 mm) white border, according to Wikipedia. The 2023 MUTCD lists 30 x 30 in for the single-lane conventional road column and also for its minimum column.[1][2]
Larger signs and other countries
The 2023 MUTCD table lists 36 x 36 in (91 cm) for multi-lane roads and expressways, and 48 x 48 in (122 cm) as the oversized size. It says that on multi-lane conventional roads the Multi-Lane column applies, and the option to use the single-lane size at 35 mph or less does not apply to STOP signs. Outside the US, the 1968 Vienna Convention proposed 600, 900 or 1200 mm signs, and the UK and New Zealand use 750, 900 or 1200 mm.[1][2]
History
Stop signs were adopted across Michigan in 1915. The first signs had black lettering on a white background and measured 24 x 24 in (61 cm). In 1922 a committee supported by the American Association of State Highway Officials met to standardise them and chose the octagon. The first Manual on Uniform Traffic Control Devices, published in 1935, detailed the sign's specifications.[2]
Did you know?
The octagon was picked as the shape of US stop signs in 1922 and has been used ever since.
Questions people ask
How big is a standard stop sign?
In the US it is 30 x 30 in (76 cm) across the flats on a single-lane road. The 2023 MUTCD lists 36 x 36 in (91 cm) for multi-lane roads and expressways, and 48 x 48 in (122 cm) oversized.[1][2]
How tall are the letters on a stop sign?
On a 30 in sign the word STOP is 10 in (25 cm) tall, with a 3/4 in white border, according to Wikipedia.[2]
Sources
- MUTCD 11th Edition (December 2023), Chapter 2B Regulatory Signs - FHWA mutcd-dr.fhwa.dot.gov
- Stop sign - Wikipedia en.wikipedia.org
