A squeaky hinge usually has friction between the pin and hinge leaves because of dirt, lack of lubrication, or slight misalignment. Start with cleaning and a suitable lubricant; if the noise returns quickly, check loose screws and whether the door is loading the hinge unevenly.
Clean visible dust and debris
Open and close the door to identify the noisy hinge and wipe around the pin. Dirt mixed with old lubricant can form an abrasive paste, so do not keep adding oil indefinitely without cleaning.
Apply a small amount of appropriate lubricant
Use a lubricant suitable for door hardware and avoid soaking wood or paint. Move the door several times to distribute it and wipe away excess so it does not attract more dust.
Remove the pin only when the hinge design allows it and the door is supported
If squeaking persists, some hinge pins can be removed to clean rust or debris. Support the door and do not force hinges with nonremovable pins or heavy doors that could shift.
Address loose screws if the door also sags
A misaligned hinge can squeak because it is working under side load. Tighten sound fasteners and repair holes that no longer grip; if the door rubs or hangs on one hinge, correct that geometry as well as lubricating.