Menu
Urgent
React2Shell security update

Web Analytics Drains Reference

Last updated September 24, 2025

If a Web Analytics Drains has been configured, Vercel will send page views and custom events from your applications to external endpoints for storage and analysis over HTTPS when your application tracks events.

The following table describes the possible fields that are sent via Web Analytics Drains:

NameTypeDescriptionExample
stringSchema version identifier
stringType of analytics event or
stringName of the custom event
stringAdditional data associated with the event
numberUnix timestamp when the event was recorded1694723400000
stringIdentifier for the Vercel project
stringIdentifier for the project owner
stringName of the data source
numberUnique session identifier12345
numberUnique device identifier67890
stringOrigin URL where the event was recorded
stringURL path where the event was recorded
stringReferrer URL
stringQuery parameters from the URL
stringRoute pattern for the page
stringCountry code of the user
stringRegion code of the user
stringCity of the user
stringOperating system name
stringOperating system version
stringClient browser name
stringType of client
stringClient browser version
stringType of device
stringDevice brand
stringDevice model
stringBrowser engine name
stringBrowser engine version
stringSDK version used to track events
stringSDK name used to track events
stringFull SDK version string
stringVercel environment
stringVercel deployment URL
stringFeature flags information
stringIdentifier for the Vercel deployment

Vercel supports the following formats for Web Analytics Drains, which you can configure when setting the Drain destination:

Vercel sends Web Analytics data as JSON arrays containing event objects:

Vercel sends Web Analytics data as newline-delimited JSON objects:

When you configure a Web Analytics Drain in the Vercel UI, you can set the sampling rate to control the volume of data sent. This helps manage costs when you have high traffic volumes.

For more information on Web Analytics Drains and how to use them, refer to the following resources:


Was this helpful?

supported.