Callus should be differntiated from wart or corn? If its callus... ill fitting shoes, orthopaedic abnormalities, walking style, obesity..etc are the aggravating factors for both corn & callus. Wart is a viral infection may affect commonly on soles need to differntiated, its resistant to the treatment. Thinking its callus , various strength of  salicylic acid creams, procedures like paring ..etc are available, proper shoes & modification of walking style...may improve .