A lubricant applicator includes a lubricant, a supply member contactable against the lubricant to supply the lubricant to a target, and a lubricant gauge to detect whether an amount of lubricant remaining is less than a threshold value. The lubricant gauge includes a rotary member rotatable about a shaft, a pressing member to press and rotate the rotary member as the lubricant is consumed, a contact part of the rotary member pressed by the pressing member, and a detection part of the rotary member opposite to the contact part across the shaft of the rotary member.