Ell
An ell is a historical unit of length that was commonly used in medieval Europe, especially for measuring textiles and cloth. Its length varied by region but was typically about 45 inches (approximately 1.143 meters).
The ell originated from the length of the arm or forearm and was often used by tailors and merchants to measure fabric. Different countries had their own versions—for example, the English ell was about 45 inches, while the Scottish ell was longer, around 37 inches.
Although obsolete today, the ell played an important role in trade and clothing production before standardized measurements became widespread.
Summary:
1 ell ≈ 45 inches (1.143 meters)
Used mainly for measuring cloth and textiles
Length varied by region and country
The ell is now largely of historical interest but reflects the origins of many modern measurement systems.
Petameter
A petameter (Pm) is a unit of length in the metric system, equal to 1 quadrillion meters (1 petameter = 10¹⁵ meters). This unit is extremely large and is used mainly in astronomy and theoretical physics to describe vast distances, such as those between stars or galaxies. For example, one petameter is about 105.7 light years. Since it measures such enormous distances, the petameter is not used in everyday life or common scientific applications—it’s mostly used in discussions about the scale of the universe.
No conversions available for length.