8.4.1 Clocking commands

C-c C-x C-i     (org-clock-in)

Start the clock on the current item (clock-in). This inserts the CLOCK keyword together with a timestamp. If this is not the first clocking of this item, the multiple CLOCK lines will be wrapped into a :LOGBOOK: drawer (see also the variable org-clock-into-drawer). When called with a C-u prefix argument, select the task from a list of recently clocked tasks. With two C-u C-u prefixes, clock into the task at point and mark it as the default task. The default task will always be available when selecting a clocking task, with letter d.
While the clock is running, the current clocking time is shown in the mode line, along with the title of the task. The clock time shown will be all time ever clocked for this task and its children. If the task has an effort estimate (see Effort estimates), the mode line displays the current clocking time against it¹ If the task is a repeating one (see Repeated tasks), only the time since the last reset of the task ² will be shown. More control over what time is shown can be exercised with the CLOCK_MODELINE_TOTAL property. It may have the values current to show only the current clocking instance, today to show all time clocked on this tasks today (see also the variable org-extend-today-until), all to include all time, or auto which is the default³.
Clicking with mouse-1 onto the mode line entry will pop up a menu with clocking options.

C-c C-x C-o     (org-clock-out)

Stop the clock (clock-out). This inserts another timestamp at the same location where the clock was last started. It also directly computes the resulting time in inserts it after the time range as ‘=> HH:MM’. See the variable org-log-note-clock-out for the possibility to record an additional note together with the clock-out timestamp⁴.

C-c C-x C-e     (org-clock-modify-effort-estimate)

Update the effort estimate for the current clock task.

C-c C-c or C-c C-y     (org-evaluate-time-range)

Recompute the time interval after changing one of the timestamps. This is only necessary if you edit the timestamps directly. If you change them with S-<cursor> keys, the update is automatic.

C-c C-t     (org-todo)

Changing the TODO state of an item to DONE automatically stops the clock if it is running in this same item.

C-c C-x C-x     (org-clock-cancel)

Cancel the current clock. This is useful if a clock was started by mistake, or if you ended up working on something else.

C-c C-x C-j     (org-clock-goto)

Jump to the headline of the currently clocked in task. With a C-u prefix arg, select the target task from a list of recently clocked tasks.

C-c C-x C-d     (org-clock-display)

Display time summaries for each subtree in the current buffer. This puts overlays at the end of each headline, showing the total time recorded under that heading, including the time of any subheadings. You can use visibility cycling to study the tree, but the overlays disappear when you change the buffer (see variable org-remove-highlights-with-change) or press C-c C-c.

The l key may be used in the timeline (see Timeline) and in the agenda (see Weekly/daily agenda) to show which tasks have been worked on or closed during a day.