Remove invalid or incorrect data

Data on Amplitude is immutable once ingested. Amplitude Data provides you with several methods to prevent invalid or incorrect data from appearing in your Amplitude analyses. You can create a drop filter, create a block filter, block events and properties, or delete events and properties. This article describes each technique, as well as the differences between them.

To permanently delete data, use Amplitude's self-service data deletion feature.

Create a drop filter

You may find you've loaded incorrect data and want to filter it out from queries. Amplitude Data's drop filters feature allows you to remove specific event data from your charts at query time. These events aren't deleted, and they can be restored to your charts simply by editing or deleting the drop filter. Drop filters don't apply to data exports.

To create a drop filter, follow these steps:

1. Make sure you’re on main, as filters aren't accessible from any other branch

2. In the left-hand sidebar, click Filters, then select the Drop Filters tab.

3. Click + Create Drop Filter to open the Filter Configuration fly-out panel.

4. Click Select event ... to choose the event you want to filter on.

5. Optionally, click + where to include any relevant properties that will refine your filter. For example, perhaps you want to filter out all purchase events that come from a specific geographical location. Simply select that location from the list of properties and set the evaluation to is not equal.

6. Specify the time range for the events you’d like Amplitude Data to drop-filter out.

7. When you’re ready, click Drop Data to initiate the drop filter.

If you want to edit or delete a drop filter, click on its name in the drop filter list. In the fly-out panel that appears on the right, make your edits and click Update Drop Filter.

Create a block filter

Block filters enable you to stop data ingestion for events and properties that you specify based on criteria you define. Blocking Amplitude from ingesting data can help you you need to act quickly before you update your code.

Block filters enable you to:

• Block events based on an event property or Amplitude property. For example, events from a specific data source.
• Block events from a specific IP address or set of IP addresses. Use this to block traffic from a test server or bad actor.
• Block events from a specific version of your application to help find and fix instrumentation issues.
• Block event or user properties that start with a particular string, or properties with numeric names to help uncover instrumentation issues.
• Block bot traffic from websites.

When you add or remove a block filter, allow up to 10 minutes for the change to take effect. As soon as the filter is active, it blocks Amplitude from ingesting matching data.

To create a block filter:

1. Ensure you're on your project's main branch in Data.
2. Click Filters in the side navigation.
3. Click + Create Block Filter.
4. Specify the project and data type (Events, Event properties, User properties, or Bot traffic). If applicable, use the available filtering parameters.
5. Click Block Data to initiate the block filter.

Block events based on property values

Block events based on the value of up to three event properties.

When you block events based on property values, Amplitude compares your filter against the raw stringified values sent to Amplitude. Knowing the data type is important in the following scenarios:

• Boolean values: If you send a property as true or false, Amplitude displays the value as "True" or "False". To use this in a Block filter, you need to specify the exact value sent as a string. In this case, true or false.
• Array values: Amplitude splits arrays into separate values for querying. Block filters compare against the stringfied raw value.

To find raw property values, use the Event Explorer to view an example of the event you want to block.

Block events and properties from your plan

Create Block filters from your Events or Properties list.

1. Ensure you're on your project's main branch.
2. In Data, navigate to the Events or Properties tab.
3. Select the Events or Properties you want to block.
4. Once selected, click Block to create the filter, and confirm the block.
5. To unblock a blocked event, repeat the previous steps and click Unblock.

Block events and properties

You can prevent Amplitude Data from ingesting data on a specific event, event property, or user property by blocking it. Amplitude Data immediately stops processing data for that event or property until you decide to unblock it.

To block an event or property, follow these steps:

1. Make sure you're in the main branch. You can only block events and properties from there.
2. Navigate to Events or Properties, depending on which one you’d like to block.
3. Find the event or property you want to block and click the checkbox next to its name.
4. If blocking an event, click the Block drop down menu, and choose either Block now or Schedule for blocking. If blocking a property, click Block.
5. A confirmation modal will appear. If you are sure you still want to block the event or property, click Block.
6. To unblock a blocked event, follow steps 1-5 and click Unblock instead of Block.

Delete events and properties in Amplitude Data

If you ingest events or properties that you no longer need, you can delete them from your plan.

When you delete an event or property, Amplitude blocks it from future ingestion and removes it from chart drop-downs to prevent future querying. The event or property doesn't count toward your monthly event volume or instrumentation limit.

Deleting an event or property doesn't remove historical data. Charts that reference a deleted event load with data from before you deleted the event and indicates the event is deleted.

Deleted user properties still appear on events that are already ingested, and you can still see them in historical user stream data.

To delete an event or property:

1. Navigate to the Events or Properties section of Amplitude Data.
2. Find the events or event properties you want to delete and click the checkboxes next to their names.
3. Click Delete.
4. Complete the verification modal.

You can undelete a deleted event or property.

1. From the status filter drop-down, select Deleted to see your deleted events or properties.
2. Find the items you want to restore and click the checkboxes next to their names.
3. Click Restore.

Delete an entire user

To delete a user entirely, use the User Privacy API. This API lets you delete a user, their events, and any associated data, and helps you keep compliant with data laws and regulations.