The now predominant profile for railway rails was designed as early as 1830 by the American John Stevens. The English engineer Charles Vignoles introduced it in Europe – and gave it his name. SJ chose Vignoles rail right from the start. However, in Vignoles' homeland, chair rail was used well into the 1940s. Compared to other rail profiles, Vignoles rail is easy to splice, easy to fasten to sleepers, stands firmly, and withstands high loads.

In Sweden, the year of introduction was used as the designation for different rail models until the 1960s. The 1855 rail was the first. It was imported from England in lengths of 7.315 metres and 6.401 metres (24 and 21 feet respectively). The weight was 30.87 kilogrammes per meter.

Initially, all rails were made of iron. Since iron is quite soft, wear was significant. After the Bessemer process for making steel was introduced in 1855, the rails began to be provided with steel-clad heads. The 1875 model was the last iron rail. Thereafter, only rails made entirely of steel were purchased.

During the 1800s, most of the rails were imported. It was not until well into the 1900s that Sweden became self-sufficient in rails.

Rail lengths and weights have gradually increased. Rails up to 108 metres in length are now manufactured. Welded rails up to 400 metres can be transported on rail transport trains. Today's standard rail for major lines, UIC-60, weighs 60.34 kilogrammes per metre – twice as much as the 1855 model. The rule of thumb is that the maximum allowable axle load may be 500 times higher than the rail weight per metre.