How can one change the timestamp of an old commit in Git?

Question

The answers to How to modify existing, unpushed commits? describe a way to amend previous commit messages that haven't yet been pushed upstream. The new messages inherit the timestamps of the original commits. This seems logical, but is there a way to also re-set the times?

Answer 1

You can do an interactive rebase and choose edit for the commit whose date you would like to alter. When the rebase process stops for amending the commit you type in for instance:

git commit --amend --date="Wed Feb 16 14:00 2011 +0100" --no-edit

P.S. --date=now will use the current time.

Afterward, you continue your interactive rebase.

To change the commit date instead of the author date:

GIT_COMMITTER_DATE="Wed Feb 16 14:00 2011 +0100" git commit --amend --no-edit

The lines above set an environment variable GIT_COMMITTER_DATE which is used in amending commit.

Everything is tested in Git Bash.

Answer 2

Use git filter-branch with an env filter that sets GIT_AUTHOR_DATE and GIT_COMMITTER_DATE for the specific hash of the commit you're looking to fix.

This will invalidate that and all future hashes.

Example:

If you wanted to change the dates of commit 119f9ecf58069b265ab22f1f97d2b648faf932e0, you could do so with something like this:

git filter-branch --env-filter \
    'if [ $GIT_COMMIT = 119f9ecf58069b265ab22f1f97d2b648faf932e0 ]
     then
         export GIT_AUTHOR_DATE="Fri Jan 2 21:38:53 2009 -0800"
         export GIT_COMMITTER_DATE="Sat May 19 01:01:01 2007 -0700"
     fi'

NOTE: When you make a commit in git the first time, both the author and committer date are set, to the same value. As soon you or someone else rebases or cherry-picks that commit, the committer date gets updated of the newly created commit.

Answer 3

A better way to handle all of these suggestions in one command is

LC_ALL=C GIT_COMMITTER_DATE="$(date)" git commit --amend --no-edit --date "$(date)"

This will set the last commit's commit and author date to "right now."

Answer 4

Just do git commit --amend --reset-author --no-edit. For older commits, you can do an interactive rebase and choose edit for the commit whose date you want to modify.

git rebase -i <ref>

Then amend the commit with --reset-author and --no-edit to change the author date to the current date:

git commit --amend --reset-author --no-edit

Finally continue with your interactive rebase:

git rebase --continue

Answer 5

I wrote a script and Homebrew package for this. Super easy to install, you can find it on GitHub PotatoLabs/git-redate page.

Syntax:

git redate -c 3

You just have to run git redate and you'll be able to edit all the dates in vim of the most recent 5 commits (there's also a -c option for how many commits you want to go back, it just defaults to 5). Let me know if you have any questions, comments, or suggestions!

Answer 6

Each commit is associated with two dates, the committer date and the author date. You can view these dates with:

git log --format=fuller

If you want to change the author date and the committer date of the last 6 commits, you can simply use an interactive rebase :

git rebase -i HEAD~6

.

pick c95a4b7 Modification 1
pick 1bc0b44 Modification 2
pick de19ad3 Modification 3
pick c110e7e Modification 4
pick 342256c Modification 5
pick 5108205 Modification 6

# Rebase eadedca..5108205 onto eadedca (6 commands)
#
# Commands:
# p, pick = use commit
# r, reword = use commit, but edit the commit message
# e, edit = use commit, but stop for amending
# s, squash = use commit, but meld into previous commit
# f, fixup = like "squash", but discard this commit's log message
# x, exec = run command (the rest of the line) using shell
# d, drop = remove commit

For all commits where you want to change the date, replace pick by edit (or just e), then save and quit your editor.

You can now amend each commit by specifying the author date and the committer date in ISO-8601 format:

GIT_COMMITTER_DATE="2017-10-08T09:51:07" git commit --amend --date="2017-10-08T09:51:07"

The first date (GIT_COMMITTER_DATE=) is the commit date, the second one (--date=) is the author date.

Then go to the next commit with :

git rebase --continue

Repeat the process until you amend all your commits. Check your progression with git status.

Answer 7

git commit --amend --date="now"

Answer 8

How to Edit Multiple Commit Dates

Other answers aren't very convenient for editing several commit dates. I've come back to this question after a few years to share a technique.

To change the dates of the last 4 commits:

git rebase -i HEAD~4

Edit the rebase as follows, inserting exec lines to modify dates as needed:

pick 4ca564e Do something
exec git commit --amend --no-edit --date "1 Oct 2019 12:00:00 PDT"
pick 1670583 Add another thing
exec git commit --amend --no-edit --date "2 Oct 2019 12:00:00 PDT"
pick b54021c Add some tests
exec git commit --amend --no-edit --date "3 Oct 2019 12:00:00 PDT"
pick e8f6653 Fix the broken thing
exec git commit --amend --no-edit --date "4 Oct 2019 12:00:00 PDT"

Update (Sep. 2021):

If you want to see the original commit date in the rebase instruction list (Git 2.6+):

git config --add rebase.instructionFormat "[%ai] %s"

Then you'll see something like

pick 4f5a371f [2021-09-08 02:56:50 -0700] Add npm events
pick 67937227 [2021-09-09 03:05:42 -0700] Fixup

Answer 9

After reading all the answers I came up with a more succinct and convenient way of editing the date of multiple commits at once without the need of rebasing interactively:

git rebase HEAD~4 --exec "git commit --amend --no-edit --date 'now'"

It changes both the committer and author dates.

Answer 10

Building on theosp's answer, I wrote a script called git-cdc (for change date commit) that I put in my PATH.

The name is important: git-xxx anywhere in your PATH allows you to type:

git xxx
# here
git cdc ... 

That script is in bash, even on Windows (since Git will be calling it from its msys environment)

#!/bin/bash
# commit
# date YYYY-mm-dd HH:MM:SS

commit="$1" datecal="$2"
temp_branch="temp-rebasing-branch"
current_branch="$(git rev-parse --abbrev-ref HEAD)"

date_timestamp=$(date -d "$datecal" +%s)
date_r=$(date -R -d "$datecal")

if [[ -z "$commit" ]]; then
    exit 0
fi

git checkout -b "$temp_branch" "$commit"
GIT_COMMITTER_DATE="$date_timestamp" GIT_AUTHOR_DATE="$date_timestamp" git commit --amend --no-edit --date "$date_r"
git checkout "$current_branch"
git rebase  --autostash --committer-date-is-author-date "$commit" --onto "$temp_branch"
git branch -d "$temp_branch"

With that, you can type:

git cdc @~ "2014-07-04 20:32:45"

That would reset author/commit date of the commit before HEAD (@~) to the specified date.

git cdc @~ "2 days ago"

That would reset author/commit date of the commit before HEAD (@~) to the same hour, but 2 days ago.

---

Ilya Semenov mentions in the comments:

For OS X you may also install GNU coreutils (brew install coreutils), add it to PATH (PATH="/usr/local/opt/coreutils/libexec/gnubin:$PATH") and then use "2 days ago" syntax.

Answer 11

Information from July 2022:

This one working amazing with current timestamp:

git commit --amend --date=now --no-edit

And this one - with any date format:

git commit --amend --date="Mon Jul 25 10:37:36 2022 +0300" --no-edit

Answer 12

To change both the author date and the commit date:

GIT_COMMITTER_DATE="Wed Sep 23 9:40 2015 +0200" git commit --amend --date "Wed Sep 23 9:40 2015 +0200"

Answer 13

I created this npm package to change date of old commits.

https://github.com/bitriddler/git-change-date

Sample Usage:

npm install -g git-change-date
cd [your-directory]
git-change-date

You will be prompted to choose the commit you want to modify then to enter the new date.

If you want to change a commit by specific hash run this git-change-date --hash=[hash]

Answer 14

if it is previous last commit.

git rebase  -i HEAD~2
git commit --amend --date=now

if you already push to orgin and can force use:

git push --force 

if you can't force the push and if it is pushed, you can't change the commit! .

Answer 15

The most simple way to modify the date and time of the last commit

git commit --amend --date="12/31/2021 @ 14:00"

Answer 16

Here is a convenient alias that changes both commit and author times of the last commit to a time accepted by date --date:

[alias]
    cd = "!d=\"$(date -d \"$1\")\" && shift && GIT_COMMITTER_DATE=\"$d\" \
            git commit --amend --date \"$d\""

Usage: git cd <date_arg>

Examples:

git cd now  # update the last commit time to current time
git cd '1 hour ago'  # set time to 1 hour ago

Edit: Here is a more-automated version which checks that the index is clean (no uncommitted changes) and reuses the last commit message, or fails otherwise (fool-proof):

[alias]
    cd = "!d=\"$(date -d \"$1\")\" && shift && \
        git diff-index --cached --quiet HEAD --ignore-submodules -- && \
        GIT_COMMITTER_DATE=\"$d\" git commit --amend -C HEAD --date \"$d\"" \
        || echo >&2 "error: date change failed: index not clean!"

Answer 17

The following bash function will change the time of any commit on the current branch.

Be careful not to use if you already pushed the commit or if you use the commit in another branch.

# rewrite_commit_date(commit, date_timestamp)
#
# !! Commit has to be on the current branch, and only on the current branch !!
# 
# Usage example:
#
# 1. Set commit 0c935403 date to now:
#
#   rewrite_commit_date 0c935403
#
# 2. Set commit 0c935403 date to 1402221655:
#
#   rewrite_commit_date 0c935403 1402221655
#
rewrite_commit_date () {
    local commit="$1" date_timestamp="$2"
    local date temp_branch="temp-rebasing-branch"
    local current_branch="$(git rev-parse --abbrev-ref HEAD)"

    if [[ -z "$date_timestamp" ]]; then
        date="$(date -R)"
    else
        date="$(date -R --date "@$date_timestamp")"
    fi

    git checkout -b "$temp_branch" "$commit"
    GIT_COMMITTER_DATE="$date" git commit --amend --date "$date"
    git checkout "$current_branch"
    git rebase "$commit" --onto "$temp_branch"
    git branch -d "$temp_branch"
}

Answer 18

If you want to get the exact date of another commit (say you rebase edited a commit and want it to have the date of the original pre-rebase version):

git commit --amend --date="$(git show -s --format=%ai a383243)"

This corrects the date of the HEAD commit to be exactly the date of commit a383243 (include more digits if there are ambiguities). It will also pop up an editor window so you can edit the commit message.

That's for the author date which is what you care for usually - see other answers for the committer date.

Answer 19

If commit not yet pushed then I can use something like that:

git commit --amend --date=" Wed Mar 25 10:05:44 2020 +0300"

after that git bash opens editor with the already applied date so you need just to save it by typing in the VI editor command mode ":wq" and you can push it

Answer 20

For updating the date of the 5 last commits to the current date (this method doesn't allow to update the initial commit):

git rebase HEAD~5 --exec "git commit --amend --no-edit --date 'now'"

For all commits after commit 95f5074…15074db2:

git rebase 95f5074…15074db2 --exec "git commit --amend --no-edit --date 'now'"

For all commits (including the initial commit):

git rebase --root --exec "git commit --amend --no-edit --date 'now'"

Add -i for the interactive mode.

Run git log --format=fuller --show-signature to validate the changes.

Run git push -f to update the remote repository (⚠️Danger zone)

There are implications. For instance:

• Commit IDs will change, so you will have to recreate tags
• You will lose original signatures
• This will use your .gitconfig, this means your key will be used for signing commits (if Git is configured to sign commits)

Answer 21

GIT_COMMITTER_DATE="Sun Nov 20 21:02 2022 +0530" git commit --amend --no-edit --date="Sun Nov 20 21:02 2022 +0530"
git push -f

Works everytime.

Answer 22

Set the date of the last commit to the current date

GIT_COMMITTER_DATE="$(date)" git commit --amend --no-edit --date "$(date)"

Set the date of the last commit to an arbitrary date

GIT_COMMITTER_DATE="Mon 20 Aug 2018 20:19:19 BST" git commit --amend --no-edit --date "Mon 20 Aug 2018 20:19:19 BST"

Set the date of an arbitrary commit to an arbitrary or current date

Rebase to before said commit and stop for amendment:

1. git rebase <commit-hash>^ -i
2. Replace pick with e (edit) on the line with that commit (the first one)
3. quit the editor (ESC followed by :wq in VIM)
4. Either:

• GIT_COMMITTER_DATE="$(date)" git commit --amend --no-edit --date "$(date)"
• GIT_COMMITTER_DATE="Mon 20 Aug 2018 20:19:19 BST" git commit --amend --no-edit --date "Mon 20 Aug 2018 20:19:19 BST"

Source: https://codewithhugo.com/change-the-date-of-a-git-commit/

Answer 23

If you want to perform the accepted answer (https://stackoverflow.com/a/454750/72809) in standard Windows command line, you need the following command:

git filter-branch -f --env-filter "if [ $GIT_COMMIT = 578e6a450ff5318981367fe1f6f2390ce60ee045 ]; then export GIT_AUTHOR_DATE='2009-10-16T16:00+03:00'; export GIT_COMMITTER_DATE=$GIT_AUTHOR_DATE; fi"

Notes:

• It may be possible to split the command over multiple lines (Windows supports line splitting with the carret symbol ^), but I didn't succeed.
• You can write ISO dates, saving a lot of time finding the right day-of-week and general frustration over the order of elements.
• If you want the Author and Committer date to be the same, you can just reference the previously set variable.

Many thanks go to a blog post by Colin Svingen. Even though his code didn't work for me, it helped me find the correct solution.

Answer 24

For those using Powershell

git rebase DESIRED_REF^ -i

$commitDateString = "2020-01-22T22:22:22"
$env:GIT_COMMITTER_DATE = $commitDateString
git commit --amend --date $commitDateString
$env:GIT_COMMITTER_DATE = ""

git rebase --continue

Credit to https://mnaoumov.wordpress.com/2012/09/23/git-change-date-of-commit/

Answer 25

Edit the author date and the commit date of the last 3 commits:

git rebase -i HEAD~3 --committer-date-is-author-date --exec "git commit --amend --no-edit --date=now"

The --exec command is appended after each line in the rebase and you can choose the author date with the --date=..., the committer date will be the same of author date.

Answer 26

In addition to Matt Montag's answer:

If you need to reset timestamp to current time after rebase command

git rebase -i HEAD~2

you can use one of these options

pick 4ca564e Do something
exec git commit --amend --no-edit --date=now
pick 1670583 Add another thing
exec git commit --amend --no-edit --reset-author

Both will work

Answer 27

There are already many great answers, but when I want to change date for multiple commits in one day or in one month, I don't find a proper answer. So I create a new script for this with explaintion, hope it will help someone:

#!/bin/bash

# change GIT_AUTHOR_DATE for commit at Thu Sep 14 13:39:41 2017 +0800
# you can change the data_match to change all commits at any date, one day or one month
# you can also do the same for GIT_COMMITTER_DATE

git filter-branch --force --env-filter '

date_match="^Thu, 14 Sep 2017 13+"              

# GIT_AUTHOR_DATE will be @1505367581 +0800, Git internal format 
author_data=$GIT_AUTHOR_DATE;                   
author_data=${author_data#@}                  
author_data=${author_data% +0800}                # author_data is 1505367581     

oneday=$((24*60*60))

# author_data_str will be "Thu, 14 Sep 2017 13:39:41 +0800", RFC2822 format
author_data_str=`date -R -d @$author_data`      

if [[ $author_data_str =~ $date_match ]];
then
    # remove one day from author_data
    new_data_sec=$(($author_data-$oneday))
    # change to git internal format based on new_data_sec
    new_data="@$new_data_sec +0800"             
    export GIT_AUTHOR_DATE="$new_data"
fi
' --tag-name-filter cat -- --branches --tags

The date will be changed:

AuthorDate: Wed Sep 13 13:39:41 2017 +0800

Answer 28

I wanted to make sure that I update my code’s copyright comments at precisely midnight, and I didn’t want to risk a tiny delay with at or cron. So, I commited the code and then:

GIT_COMMITTER_DATE="Fri Jan 1 00:00:00 2021 +1000" git commit --amend --no-edit --date="Fri Jan 1 00:00:00 2021 +1000"

(Or perhaps even set the UTC offset to 0? Decisions… ) Now I can push!

Happy new year, everybody 🥳

Answer 29

I have recently needed this and made my own script looking a lot like git-redate

However my scripts does the minimal modifications and takes a lot less time to rewrite (if you need to update) many commits as it does them all at once

change_git_history

Actually this allows to change commit messages too

Explaination:

The scripts concatenates a bunch of bash if-expression looking like so

Here are the ones modifiying the commit date

if [ "$GIT_COMMIT" = "$com_hash" ]; # com is commit
then
    export GIT_AUTHOR_DATE="$com_date";
    export GIT_COMMITTER_DATE="$com_date";
fi;

Here are the ones modifiying the commit message:

if [ true = false ]; # impossible
then
    : # pass
elif [ "$GIT_COMMIT" = "$com_hash" ];
then
    sed 's/.*/$com_msg_esc/g' # replace content with new content
else
    cat - # returns previous content
fi;

And we push all the update using

git filter-branch -f \
    --env-filter "$UPDATES" \
    --msg-filter "$MESSAGES" \
    -- "$REV"

(doc is here filter-branch man)

Answer 30

Here is how you can commit to past dates so it gets reflected both in commit date as well as in your contribution table

If you use git log --pretty=fuller you will see that the commit has:

• Author/AuthorDate - for contribution table
• Commit/CommitDate - for commit date (inside repository)

1. git commit --amend --date="Mar 01 10:00 2024 +0600" --no-edit
2. GIT_COMMITTER_DATE="2024-03-01 10:00:00" git commit --amend --no-edit
3. git push --force

Visual Example