[GA4] Modify and create events via the user interface

You can use the user interface to change existing events and create new events. For example, you can

• Rename an event so that the same event name is used across properties and data streams
• Fix a typo that's causing a measurement error
• Trigger a new event based on conditions you set, and mark the new event as a conversion

You need the Edit permission to modify and create events.

In this article:

• Modify vs Create
• Modify an event
• Create an event
• Create a conversion event
• Event name rules
• Reorder event modifications
• Limits

Modify vs Create

Use Modify to overwrite an event. Use Create to trigger a new event based on conditions that you set.

Modify an event to overwrite it

 In the example below, you rename pub_article to publish_article. For all data collected after this change,  publish_article will appear in your reports instead of pub_article.

Modify event

Modification name

Change pub_article to publish_article

---

Matching conditions

Parameter	Operator	Value
event_name	equals	pub_article

---

Modify parameters

Parameter	New value
event_name	publish_article

Create to trigger a new event

Creating an event is useful when you need to trigger an event based on conditions that you specify, but you don't want any existing events to change. This is particularly useful when you need to create a conversion event.

In the example below, both pub_article and publish_article will appear in your reports, for all data collected after this change. 

Create event

Custom event name

publish_article

---

Matching conditions

Parameter	Operator	Value
event_name	equals	pub_article

Modify an event

1. In the left pane, click Configure, then Events.
2. Click Modify event.
3. If your property has more than one data stream, you will be asked to select a data stream.
4. Click Create.
5. Under Modification name, enter a description of the change you are making, e.g. "Rename pub_article to publish_article". Modification names must be unique.
   The Modification name will appear in your list of event modifications, so provide text that describes the purpose of this modification. You may wish to reorder the sequence of your modifications; descriptive text makes it easier to recognize which modifications depend on other modifications.
6. Under Matching conditions, enter one or more conditions that specify when the modification should take place. For example, the following condition specifies that the modification should take place whenever an event named "pub_article" is sent to the property.
   Matching conditions

   Parameter	Operator	Value
   event_name	equals	pub_article

7. Under Modify parameters, specify what change should be made. For example, the following specifies that event name should be changed to "publish_article". More examples
   Modify parameters

   Parameter	New value
   event_name	publish_article

8. Click Save.

Modifications don't apply to historical data. It may take some time after saving the modification before it begins to take effect on new data you collect. See below for additional limits.

"Modify parameters" examples

Change a parameter value

To change an event parameter value, select the parameter in the Parameter field, then enter the value you want to use in the New value field. For example, to change the value of level_name to "Scary dungeon", select the level_name parameter, then enter the new value:

Modify parameters

Parameter	New value
level_name	Scary dungeon

Copy a parameter value

You can replace one parameter's value with another parameter's value. To do this, enter the other parameter's name enclosed in double brackets in the New value field.

Modify parameters

Parameter	New value
level_name	[[other_parameter]]

For example, suppose you find a typo in a parameter name: instead of level_name, an event was implemented with a lvl_name parameter. You can fix this by first copying the misspelled parameter to the correct parameter. 

Modify parameters

Parameter	New value
level_name	[[lvl_name]]

Remove an event parameter

You can delete parameters you don't need or want. To do this, set the parameter value to blank.

Modify parameters

Parameter	New value
lvl_name

Rename an event

If you rename an event that is already marked as a conversion, that event will no longer be a conversion. If you modify event parameters but do not change the name, the event remains a conversion.

Event names must follow these rules.

To change an event's name, in the Parameter field, select event_name, and enter the new name in the New Value field. For example, you can rename a "buy" event to "purchase".

---

Matching conditions

Parameter	Operator	Value
event_name	equals	buy

---

Modify parameters

Parameter	New value
event_name	purchase

New event names must conform to the event naming rules described below.

You can change multiple parameters at once.

• To change another parameter, click Add modification.
• To remove a condition, on the right, click .

Edit Events in Google Analytics 4 properties

Create an event

1. In the left pane, click Configure, then Events.
2. Click Create event.
3. If your property has more than one data stream, you will be asked to select a data stream.
4. Click Create.
5. Under Custom event name, enter the name you want this new event to have. Event name rules
6. Under Matching conditions, specify when this new event should be triggered. Example
7. If you want this new event to have the same parameters as the event that you specified under Matching conditions, select the Copy parameters from the source event checkbox. For example, if you want your new event to be triggered whenever a page_view event is sent, and you want your new event to have the same parameters as page_view, select this checkbox.
8. If you are copying parameters from the source event, specify any changes you want to make to the parameter values. For example, if your new event is triggered whenever a page_view event is sent with page_title of "Confirmation", and you want the new event to substitute a different value for page_title, specify that change here.

"Matching conditions" example

Identify the existing event or parameter you want to use as the trigger for your new event. 

Let's say you want to create custom event called "large_purchase" whenever a purchase event is sent with a value of $100 or more.

1. Enter "large_purchase" as the Custom event name.
2. Enter the matching conditions.
3. Copy the original event's parameters to the new event.

Custom event name

large_purchase

---

Matching conditions

Parameter	Operator	Value
event_name	equals	purchase
value	greater than or equal to	100

Parameter configuration

✓ Copy parameters from the source event

In this example, the original purchase event remains, and your new "large_purchase" event is also logged when the value of the purchase event is greater than or equal to 100.

Create Events in Google Analytics 4 properties

Create a conversion event

Using "Create" is useful when you need to create a conversion event. Let's say you want to create event called "confirm_reservation" that is triggered whenever a page_view event is sent with a page_title value of "Confirmation": 

1. In the left pane, click Configure, then Events.
2. Click Create event.
3. If your property has more than one data stream, you will be asked to select a data stream.
4. Click Create.
5. Under Custom event name, enter a name for your conversion event (e.g. "confirm_reservation")
6. Under Matching conditions, specify when this new event should be triggered.
   Matching conditions

   Parameter	Operator	Value
   event_name	equals	page_view
   page_title	equals	Confirmation

7. Click Create.

Now that you have created the event, mark it as a conversion event:

1. In the left pane, click Configure, then Conversions.
2. Click New conversion event.
3. Under New event name, enter the name of the new event you created (e.g. "confirm_reservation").
4. Click Save.

Event name rules

• Event names are case sensitive. For example, my_event and My_Event are two distinct events.
• Use only letters, numbers, and underscores. Don't use spaces. Names must start with a letter.

• You can't use reserved prefixes and event names for custom events. See the list below.

  Reserved prefixes and event names

  This list is not exhaustive and may be updated periodically. If you try to use a reserved prefix or name, Analytics will display an error message.

  Web

  Prefixes

  • _ (underscore)
  • firebase_
  • ga_
  • google_
  • gtag.

  Event names

  • app_remove
  • app_store_refund
  • app_store_subscription_cancel
  • app_store_subscription_convert
  • app_store_subscription_renew
  • first_open
  • first_visit
  • in_app_purchase
  • session_start
  • user_engagement

  Mobile (Android and iOS)

  Prefixes

  • _ (underscore)
  • firebase_
  • ga_
  • google_
  • gtag.

  Event names

  • ad_activeview
  • ad_click
  • ad_exposure
  • ad_query
  • ad_reward
  • adunit_exposure
  • app_background
  • app_clear_data
  • app_exception
  • app_remove
  • app_store_refund
  • app_store_subscription_cancel
  • app_store_subscription_convert
  • app_store_subscription_renew
  • app_update
  • app_upgrade
  • dynamic_link_app_open
  • dynamic_link_app_update
  • dynamic_link_first_open
  • error
  • firebase_in_app_message_action
  • firebase_in_app_message_dismiss
  • firebase_in_app_message_impression
  • first_open
  • first_visit
  • in_app_purchase
  • notification_dismiss
  • notification_foreground
  • notification_open
  • notification_receive
  • notification_send
  • os_update
  • session_start
  • session_start_with_rollout
  • user_engagement

Reorder event modifications

Event modifications are applied to your data in the order they appear in the modifications list. This order can be important if you have modifications that rely on each other.

For example, if you rename an event in Modification 1 and use that new name as the basis for creating another event in Modification 2, then you need the modifications to execute in the order of Modification 1 > Modification 2. If those modifications are listed out of order, then Modification 2 will fail.

To reorder event modifications:

1. In the left pane, click Configure, then Events.
2. Click Modify Event.
3. If your property has more than one data stream, you will be asked to select a data stream.
4. In the list of Event modifications, click Reorder.
5. Drag a modification from one position in the list to another as needed.
6. Click Apply.

Limits of event modifications and created events

• Modified and created events don't apply to historical data.
• You can create up to 50 modifications to existing events and up to 50 created events.
• Modifications require time (generally within an hour but possibly longer) before taking effect.
• Modifications are executed client side before data is sent to Analytics for processing.
• Modifications execute in the order they appear in the Event modifications list.
• Modifications are processed before created events are processed.
• You can't reorder created events.