To Unlock and Connect to Google please see the "Desktop Guide"

Video Instructions for Using GCalToolkit

Important Notes on using GCalToolkit

GCalToolkit is a VERY POWERFUL tool, and should be used with caution: Please BACKUP your Google calendar to iCal before you start (in Google Calendar "Settings" > "Calendars" > "Export"), and take the time to learn how GCalToolkit works before you use it on mission critical calendars.

The Google Quota:Google Calendars has a daily (and maybe weekly) quota system that limits accounts to approximately 18,000 events downloaded/edited/deleted within a 24 hour period. Accounts with mass duplication issues will often hit this quota limit during faulty syncing and exhibit unusual behaviour such as slowness, problems creating new calendars, and problems exporting a backup as zipped iCal files (the surest sign of quota problems). The solution is to disable ALL syncing with Google Calendar (or simply change your Google Account password), and be patient. Google will usually reset your quota within 24 hours, at which time you should immediately create an iCal backup of your calendar data (regardless of duplicates), and then start cleaning up your Google Calendar with GCalToolkit as described on the rest of this website.

If you experience problems when using GCalToolkit on large calendars then please bear this in mind - if the problem persists please send me an email or use the contact page to get in touch, and include as much detail as possible about your situation.


If you use Outlook®, iCal, Sunbird or any smartphone (Android, iPhone, Blackberry...) that can sync to Google, then you can set up 2-way sync between your calendar and Google Calendars to take advantage of the power of GCalToolkit - this means that you can delete duplicates, mass edit, mass delete, search/replace, shift events, spreadsheet export etc. in ANY CALENDAR SOFTWARE using GCalToolkit. Please read the DESKTOP GUIDE for more information on the full editing power of GCalToolkit.

If you have an iCal (.ics) or .csv calendar file with duplicates that you need to remove, or multiple events that you need to delete, simply import the file into a blank Google Calendar, then use GCalToolkit to remove the duplicates, or edit/delete multiple events. When you are finished, export the result as a new iCal (.ics) file to be imported into whichever calendar software you use. If you use the Mac "Calendar" software formerly known as iCal... you can either export an iCal (*.ics) file and import it to Google Calendar for editing with GCalToolkit, or set up 2-way sync with Google Calendar instead.

For information on downloading and installing GCalToolkit please visit the Download page, or simply click the big button at the top of this page to download the correct version for your operating system.

Use GCalToolkit to Repair unlimited Google Calendars 

  • FREE TRIAL: DOWNLOAD the desktop software
  • FULL VERSION €29: 1 year licence + free updates + online support
  • FULL VERSION €49: LIFETIME* licence + free updates + online support
  • ENTERPRISE €99: As above + 10 installs, priority support and your own API Quota
  • Secure payment on PayPal - most Credit Cards accepted, no Paypal account needed
  • GCalToolkit runs on nearly any device: Windows, macOS and Linux
  • GCalToolkit works on all versions of Microsoft WINDOWS (JAVA 1.7, 1.8 or 9 required)
  • Unlimited help & technical support  for all FULL VERSION users
  • Help & advice  for ANY Google Calendar problem!

 The FULL VERSIONS are valid for one household (or a few business users) on unlimited Google Calendars. The Full Version allows you to process ALL EVENTS on ALL your Google Calendar agendas.

Please keep your account details private; Google places a limit on the number of daily requests software such as this can perform, so it's not fair to everyone else if you hand out your details to colleagues and friends. Not to mention that the GCalToolkit server will detect multiple installations. Accounts may be suspended if misused, so please, one household... one or two business users... otherwise you should purchase an "Enterprise" license.

Please Note: If ever support requests exceed a certain limit I will have to remove the "Lifetime" deal, so get it now while stocks last!

The TRIAL VERSION allows you to process 500 events

(* i.e the lifetime of GCalToolkit)


New Features

GCalToolkit has many fantastic new features to help you repair and maintain Google Calendars, such as fully customizable column views and spreadsheets, adding prefixes/suffixes, case sensitive filtering (and regex support), mass editing of busy/free status, mass editing of the "guests can modify" field, sorting by resource owner, better Google session handling, a "shift" events option in the "Copy/Move" menu to allow you to duplicate groups of events (such as a work shift) that do not lend themselves to regular repeat event rules... and many more improvements and additions to make calendar maintenance and repair with GCalTooolkit easier and more powerful than ever before.


Q: What is the easiest way to delete all my Duplicates from Google Calendar and synced devices?

A: Install and run GCalToolkit, follow the simple steps to load your Google Calendar, check the number of duplicates detected, then click "SYNC to GCAL" and wait. That's it!

Q: What does "Quota Restricted" mean?

A: Google Calendars has a mysterious quota system that limits accounts to approximately 18,000-20,000 events created/edited/deleted within a 24 hour period (although it is sometimes 9,000 events, and there may be weekly quotas too).  If you experience problems when using GCalToolkit on large calendars, especially if you have had syncing problems that created duplicates, then please bear this in mind. Quota is usually reset by Google every 24 hours, although some users with very large calendars (>20,000 events) and sync problems have sometimes had to wait up to 9 days for the quota to be reset... Symptoms of Quota problems include failed GCalToolkit downloads, failed deletes/edits, sluggish calendar behaviour in the browser, problems creating new calendars, problems "Exporting" Google calendars in "Settings" > "Calendars". 

if the problem persists please use the contact page to submit a support request, including as much detail as possible about your problem. 

Q: I can't even "Export" my calendars from Google Calendar Settings > Calendars!

A: This is the most sure sign of the quota problems described above - as you approach the quota limit, GCalToolkit may only be able to download parts of your calendar even though browser behaviour appears normal; if you are unable to "Export" in a browser then you have a serious quota problem - please contact me for information on who to contact, where to leave help requests, and exactly what to say.

Q: GCalToolkit is not working, and I do not think it is a Quota problem.

Please check that your firewall or other security software is not blocking GCalToolkit from accessing the internet, and that you have a stable internet connection. Office networks can be troublesome - in some cases you may have to ask your network administrator to modify the network settings to allow the Desktop version of GCalToolkit to work correctly.

Q: How do I backup my Google Calendar, and share it?

Click HERE to watch a short video that shows how to download an iCal backup of your Google Calendar, and share it with GCalToolkit at if necessary.

Q: How do I delete all my Duplicates using the Desktop Software?

A: When you download a calendar all the duplicates are automatically marked as "Duplicates" and "To Be Deleted".  When you click "Sync to Google" all the duplicates that have been detected (within the events that you downloaded) will be deleted from Google. The total number of events, and the number of duplicates is displayed top right - and you can click "Preview Changes" to see a list of the duplicates that will be deleted before you Sync.

If you change your mind and wish to restore the duplicates that you deleted, remove all filters and click "Restore Visible Deleted" - the duplicates that were previously marked "Deleted" will now be marked "To Be Restored" (click "Preview Changes" to check), and will be restored when you next click "Sync to Google".

If your duplicates are not detected, please click "Relax Duplicates" in the "Options" menu.  This will relax the duplicate detection rules to include any events with the same title & start time - sometimes you may have duplicates that are not detected because the repeat rule is formulated slightly differently by some syncing software, or other reasons; this option will ignore these differences - use with caution because the repeat rules are no longer compared with this option, so if you have single events duplicating a repeat event it is advisable to check manually that it is indeed the singles that are to be deleted, and not the repeat. You can use the "Event" type filter for this purpose (eg list only repeats), or list events in alphabetical order by clicking the "Title" column header, scroll through and check that for each repeat to be deleted there is no identical single below it.


Q: My Calendar is not in Google Calendars - can I still use GCalToolkit to remove duplicates and edit my calendar?

A: Yes. If you are use Outlook®, iCal, Sunbird or any smartphone (such as iPhone, Blackberry or Droid) that can sync to Google, then set up 2-way sync between your calendar and Google Calendars to take advantage of the power of GCalToolkit - this means that you can delete duplicates, mass edit, mass delete, search/replace etc. in ANY CALENDAR SOFTWARE using GCalToolkit.  Please see Google Sync or gSyncit (Outlook only) for more information on how to sync with Google Calendars.

Alternatively, if you have an iCal (.ics) or .csv calendar file with duplicates that you need to remove, or multiple events that you need to delete, simply import the file into a blank Google Calendar, then use GCalToolkit to remove the duplicates, or edit/delete multiple events.  When you are finished, export the result as a new iCal (.ics) file to be imported into whichever software you choose to use.


Q: Today I imported/synced another Calendar to Google and now my calendar is a complete mess! Can GCalToolkit help?

A: Yes!   GCalToolkit can filter events by the "Created" date/time to delete a specific Import/Sync session (see "Delete Selected Events" below).  

For example, if a failed import attempt mixed two calendars together in a single Google Calendar, you can delete all events that were created by the failed import without affecting your pre-existing data, even if the dates and times are all mixed up together.  Or, if you sync another calendar to your Google Calendar and then need to delete data that has been mixed in with your existing data, simply load up your Google Calendar in GCalToolkit, and filter the events by "Created" date and click the "Delete Selected Events" button in GCalToolkit to mark all the highlighted events for deletion and then "Sync to Google". Hey presto! All events created during the last faulty sync/import will be deleted leaving all your previous data intact. Please note that the "Created" column refers to the date and time that an event was initially created in Google Calendars - only events that are created (not modified) during syncing, and any events created during an import, can be deleted in this way.


Q: I made changes to my Google Calendar using GCalToolkit Desktop Software, closed the program then went to Google Calendars in my browser and saw that I had made mistakes - what can I do?

A: You did make a backup before you started, didn't you?! If you are using GCalToolkit 1.5 then as long as you saved your session when you quit the program you can open GCalToolkit, choose "Continue Session" and select the calendar that you edited earlier.  This will bring up the events window exactly as it was when you left the program. You can now undo any changes that you made earlier and "Sync to Google" - for example, if you had deleted events then you should choose "Restore Visible Deleted" (when no filters are applied) from the EDIT menu to restore all the deleted events. If you edited text for events, then you can undo all your text edits using "Undo Visible Text Edits" (or filter first to undo only some of the edits) and the "Sync to Google".

Please note that if you have edited your Google Calendar manually in your browser since you used GCalToolkit to edit/delete then you may see unexpected results because GCalToolkit is trying to work with an outdated copy of your calendar. However, you will still be able to undo all the changes that you made in GCalToolkit if you have only added new events to your Google Calendar as this has no effect on the data that you edited/deleted with GCalToolkit.

If you are using version 2.x then there is not "Undo" - but you can always start again by deleting your calendar, and importing your backup iCal (.ics) file.  If the file is larger than about 2MB then you may have to split the iCal file into several parts in a text editor, preserving the header information (up to END:VTIMEZONE) and the last line of the calendar (END:VCALENDAR). Please contact me if you need any help with this.


Q: I'm using the trial version of the Desktop Software to delete my duplicates - why can I still see some duplicates this month?

A: The trial version only downloads 500 events:  any repeat event from BEFORE this period will NOT display, and if these are duplicated then they will not be detected.  To be 100% sure that all your duplicates are removed, please purchase and unlock the full version - if necessary click the "Relax Duplicates" option in the "Options" menu.

Q:  Can I change the order in which the events are listed in GCalToolkit?

A: Yes. You can click at the top of most columns to order the events - for the title, summary and location columns this will put the events in alphabetical order; click again to reverse the order. Under "Events" you can choose whether to display only all day events, only all day repeats, only singles, only timed singles... 


Q: I get an error message when trying to load my calendar.

A: Google Calendars servers are sometimes busy... so if you see ERROR 403 or 404 please wait a minute and try again.  If the problem persists for a few hours then you should check that you have a stable internet connection, and that nobody else is logged in and editing your Google Calendar account.  If that doesn't help, try another Google Calendar to see if that particular Google Calendar has a problem - you may have corrupt events or another issue that is preventing GCalToolkit from downloading that calendar. Please do not hesitate to contact me for help on the contact page, including as much detail as possible about your problem.


Q: How do I "Unlock" GCalToolkit Full Version?

A: First you need to register on this site (use "Login with Google" for the easiest registration option) and follow the payment instructions. All payments are made on Paypal for security reasons - but you do not need a PayPal account to purchase GCalToolkit; most credit cards are accepted too. Once your payment has cleared you can Unlock as follows:

1) Install and run GCalToolkit Trial Version
2) Click "Unlock"
3) Enter the USERNAME, PASSWORD and EMAIL that you used to register on this website before payment.
4) Click "UNLOCK" and restart GCalToolkit.


Q: I registered, purchased and "Unlocked", but GCalToolkit is still in Trial Version. What should I do?

A: Choose "Disconnect" from the main window, and try again. If that still does not work, please contact me on the "Contact" page for help with details of your system and any error messages.

Q: I purchased GCalToolkit but I would like a refund.

A: Please get in touch explaining exactly why you wish a refund:  refunds are accorded on an individual basis depending on how long you have been using the software and how politely you ask, so please provide as much information as possible to justify your request.


Q: I paid for GCalToolkit by mistake and have never unlocked it - can I get a refund?

A: If you have never unlocked GCalToolkit full version then you are of course entitled to a full refund, no questions asked.


Q: Will you communicate my email address to others?

A: Never. You may get the occasional update from GCalToolkit, but nothing else.

Q: Where can I download GCalToolkit for Google Calendar and synced devices?




 Click here to visit the detailed Download page


Concerned about security? Visit SOFTPEDIA:

Softpedia guarantees that GCalToolkit is 100% CLEAN, which means it does not contain any form of malware, including spyware, viruses, trojans and backdoors. not affiliated with or endorsed by Google Inc.
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