How are the dimensions of angle iron measured? Answer: The dimensions of angle iron are measured by the length of the legs and the thickness of the steel. For example, an angle iron with dimensions 50mm x 50mm x 6mm has two legs each 50mm long and a thickness of 6mm. https://medium.com/@marketingsteel6/ms-tmt-bar-prices-an-in-depth-guide-to-cost-and-purchasing-strategies-b72b9457db5a