OSX: How to change a file’s modified and creation date

Date Format Key:
YYYY – The year (the first two digits/century can be omitted).
MM – The month of the year, from 1 to 12.
DD – The day of the month, from 1 to 31.
hh – The hour of the day, from 0 to 23.
mm – The minute of the hour, from 0 to 59.

How to change the date modified attribute of a file?
1. Open up the Terminal application (/Applications/Utilities/Terminal.app) or if you prefer use iTerm.

2. Type this into Terminal (without hitting enter/return) replacing YYYYMMDDhhmm with the desired date information:
touch -mt YYYYMMDDhhmm

3. Open a Finder window and locate the file you wish to modify and drag and drop it into the Terminal window. Here’s an example of what should be typed into the Terminal at this point:
touch -mt 200801120000 /Volumes/Mac HD/Pictures/somefile.jpg

200801120000 in the example above represent “January 12, 2008 12:00 AM” or my 21st birthday. Make sure to change 200801120000 to the date you want and to replace /Volumes/Mac HD/Pictures/somefile.jpg with the proper path to the file you wish to alter the date for.

4. If all is in order press the return key.

How to change the date created attribute of a file?
Warning: This will change both the date modified and date created attributes.

1. Open up the Terminal application (/Applications/Utilities/Terminal.app) or if you prefer use iTerm.

2. Type this into Terminal (without hitting enter/return) replacing YYYYMMDDhhmm with the desired date information:
touch -t 201212211111

3. Open a Finder window and locate the file you wish to modify and drag and drop it into the Terminal window. Here’s an example of what should be typed into the Terminal at this point:
touch -t 201212211111 /Volumes/Mac HD/Pictures/somefile.jpg

201212211111 in the example above represent “December 21, 2012 11:11 AM” or the end of the 5,125 years that comprise the “Great Cycle” in the sacred Tzolk’in calendar of the Maya (and you can relax I don’t think the world’s gonna end then!). Make sure to change 201212211111 to the date you want and to replace /Volumes/Mac HD/Pictures/somefile.jpg with the proper path to the file you wish to alter the date for.

4. If all is in order press the return key.

Below is supplementary information on how to batch modify/update/change files using the commands above.

How to batch update the date modified attribute of multiple files?
1. Make sure all the files you want to modify are in the top directory of the same folder. Don’t store files in this folder if you don’t want them to be modified.

2. Open up the Terminal application (/Applications/Utilities/Terminal.app) or if you prefer use iTerm.

3. Type this into Terminal (without hitting enter/return) replacing YYYYMMDDhhmm with the desired date information:
touch -mt YYYYMMDDhhmm

4. Open a Finder window and locate the folder containing the files you wish to modify and drag and drop it into the Terminal window. Here’s an example of what should be typed into the Terminal at this point:
touch -mt 200801120000 /Volumes/Mac HD/Pictures/Album

5. Add /* to the end of the command. If you’re only targeting a specific file type include its extension (e.g. /*.jpg or /*.png). Your command should look something like this:
touch -mt 200801120000 /Volumes/Mac HD/Pictures/Album/*

6. If all is in order press the return key.

How to batch update the date created attribute of multiple files?
Warning: This will change both the date modified and date created attributes.

1. Make sure all the files you want to modify are in the top directory of the same folder. Don’t store files in this folder if you don’t want them to be modified.

2. Open up the Terminal application (/Applications/Utilities/Terminal.app) or if you prefer use iTerm.

3. Type this into Terminal (without hitting enter/return) replacing YYYYMMDDhhmm with the desired date information:
touch -t 201212211111

4. Open a Finder window and locate the folder containing the files you wish to modify and drag and drop it into the Terminal window. Here’s an example of what should be typed into the Terminal at this point:
touch -t 201212211111 /Volumes/Mac HD/Pictures/Album

201212211111 in the example above represent “December 21, 2012 11:11 AM”. Make sure to change 201212211111 to the date you want and to replace /Volumes/Mac HD/Pictures/Album with the proper path to the folder containing the files you wish to alter the date for.

5. Add /* to the end of the command. If you’re only targeting a specific file type include its extension (e.g. /*.jpg or /*.png). Your command should look something like this:
touch -t 201212211111 /Volumes/Mac HD/Pictures/Album/*

6. If all is in order press the return key.

By: D. Stern-Sapad