This page summarizes how to use this site.


GriCal (which is a short form for Grid Calendar) is an open web where people store quickly a few information about interesting events, so that others can also easily know about them. GriCal also makes easy and fast to get notified and store interesting events in its own external calendars.

GriCal offers its content as free content allowing its reuse by any party under the conditions of the CC-BY-SA license. Its source code is Free Software and thus respects the Open Knowledge Definition and the Open Software Service Definition of the Open Knowledge Foundation.

Events in GriCal can be edited by anyone like pages of the Wikipedia. The description of an event is rendered using ReStructuredText syntax.

You can subscribe to an event (or to the result of filters) to get notified of any change, comment, or new event matching a filter.


GriCal has groups. A group consist of some users and events. Groups allows its users to create lists of events to monitor them or to offer them on another platform.

Searches and filters

  • Searches are done by default on the fields title, acronym, tags, city and country.
  • All given words must appear in at least one of the fields.
  • Search results contain also related events (with similar tags), unless one or more of the special search restrictions are used (like # for tags, see bellow)
  • Dates in ISO-format ( yyyy-mm-dd ) restrict the query to events with dates from the oldest to the newest, including events with a deadline in the range and events taking place during the range. If only one date is provided (instead of two or more) only events with a matching date (start, end or a dateline) are shown. Example: 2011-01-01 2011-12-31
  • If there is no date in the query and the broad operator is not used, only future events are showed.
  • Tags ( #tag_name ) restricts the query to events with these tags. Example: #linux
  • Groups ( !group_name ) restricts the query to events of the group. Example:!ffii
  • Words starting with a + restrict the query to events matching the word in the fields title, acronym, city and country without related events. Example: +software
  • The string `` | `` (space pipe space) can be used to concatenate results of different searches (logical or). For example #linux | #foss will search for all future events with the tag linux or foss or both.
  • Searches starting with `` * `` (asterisk space) makes the search broader, including past events (if no dates are specified), text in the description, URLs (name and URL), sessions (name) and deadlines (name). Example: *
  • Locations (@location) restricts the query to events within the given location. Location terms must be added at the end of the query (spaces in the name of locations are possible like @Los Angeles). When given a distance, km (kilometers) and mi (miles) are allowed as units. There are four possibilities:
  • Giving a simple word ( @word ) which is looked up in the fields city or country. Example: @berlin
  • Giving the name of a place and a distance. @london+100 would look 100 kilometers around the center of the most relevant place with the name london (being it London in Great Britain). The country can be specified with e.g. @london,ca (the most relevant city with the name London in Canada).
  • Giving a coordinate and a distance ( @52.55247,13.40364+500km ).
  • Giving four coordinates defining a rectangle: longitude_west, longitude_east, latitude_north, latitude_south. Example: @13.324,13.463,52.5503,52.4701.
  • The operator = restrict the search to one single event, the one having the number which follows the operator (example =123). This can be used for e.g. sending a list of some events as a URL and showing them on a map, example:
  • Any search can be saved as a filter by logged-in users. To be able to log-in you need to register. An email will be sent in the process with a URL that you need to click.
  • You can select to get notified of new events matching one of your filters.
  • The result of searches also have a RSS feed which can be subscribed even by non-logged-in users.
  • The result of searches also have an iCalendar file which can be imported in external calendars.
  • Both the RSS feed and the iCalendar file will contain in the future new events.

Events as text

Events can be submitted per email to event ät The subject of the email is ignored. Example of the body of an email:

title: Grical presentation
start: 2010-12-29
tags: calendar software open-source gridmind grical

You can optionally include more data in the submission. Example:

acronym: GriCal
title: Grical presentation
start: 2010-12-29
starttime: 10:00
end: 2010-12-30
endtime: 18:00
tags: calendar software open-source gridmind grical
address: Gleimstr. 6, Berlin 10439, DE
coordinates: 52.55247, 13.40364
    2009-11-01    visitor tickets
    2010-10-01    call for papers
timezone: 60
    2010-12-29    10:00-11:00    first presentation
    2010-12-29    15:00-16:00    second presentation
    2010-12-30    15:00-16:00    third presentation

Grical will be presented

The field description must be the last one and its content can contain multiple lines. The content is rendered as ReStructuredText.

Recurring events

A recurring event is one that happens again after a period of time. For instance a weekly or monthly meeting.

It is possible to create and edit recurrences of an event in GriCal by using the web interface: edit the event and select recurrences

It is also possible to add recurrences in GriCal by editing an event as text, but it is not possible to edit its recurrences. Example of adding two recurrences:

title: Grical presentation
start: 2010-12-29
tags: calendar software open-source gridmind grical

Notice that the recurrences will have the same data except for the start date, the deadlines and the sessions.

Event history and event deletions

Since events can be modified by anyone, including anonymous (not logged-in) users, GriCal stores (remembers) all revisions (states) of events. All revisions of an event is called history, like the history of an entry in the Wikipedia.

Only logged-in users can delete or revert an event to a previous revision.

When an event is deleted, it is possible to indicate another event containing the information of the deleted event. Users trying to access the deleted event will be then redirected to the other one.


GriCal content can be integrated in external pages. See the wiki page about our API

GriCalDroid (Android App)

We have an Android app that allows to search and displays the result as a list, on a map or in a calendar.

To use GriCalDroid, Download GriCalDroid to your phone and install it.