Magnetic recording medium

A magnetic recording medium comprising:

• a magnetic layer;
• an underlayer;
• a base layer;
• and a back layer, wherein
• a surface on a side of the magnetic layer has a magnetic layer side surface kurtosis of 3.0 or more,
• a surface on a side of the back layer has a back layer side surface kurtosis of 2.0 or more,
• the surface on the magnetic layer side has arithmetic average roughness Ra of 2.5 nm or less,
• the base layer includes a polyester as a main component,
• the magnetic recording medium has an average thickness tT of 5.6 μm or less,
• the magnetic recording medium includes a lubricant, the lubricant includes a fatty acid and a fatty acid ester, and a mass ratio between the fatty acid and the fatty acid ester extracted by hexane satisfies fatty acid/fatty acid ester≤0.6, and
• the magnetic recording medium has pores, and the pores have an average diameter of 6 nm or more and 11 nm or less when the diameters of the pores are measured in a state where the lubricant has been removed from the magnetic recording medium and the magnetic recording medium has been dried,
• wherein the magnetic layer side surface kurtosis and the back layer side surface kurtosis are determined based on an ISO 25178 standard, and
• wherein the magnetic recording medium is tape-shaped.