BatchTouch
BatchTouch is a utility that allows you to change the date of file and folder creations and/or modifications. BatchTouch allows you to modify the creation or modification dates of multiple files and folders at once. The user can choose the type of items they want to modify, whether or not they want to process the contents of the folders, and whether or not to change the creation, modification, or both. It is possible to modify the date, the time or both. It is possible to apply absolute values and offsets to both date or time. This means that you can add/subtract a specified number of days, hours, minutes or seconds to/from the creation and modification dates. It is possible to add/subtract a specific number of days, hours or minutes to/from the creation/modification date of any item.
The software is free but it is donationware. To support development, please consider donating.