All /{website-id}/field-testing endpoints accept a large number of filters that can be used to drill down to highly specialized reports. This page describes each filter.

Filter syntax

The filters are added to the REST API call as querystring parameters:


Multiple values

If a filter has multiple values, simply separate the values with a plus sign:


Negative values

If you want to add "does not equal" or "has none of the following" filters, simply start the value with a tilde (~) sign. This example means "everything BUT Chrome and Edge browsers":


Combining filters

You can add many filters in one report, simply by adding multiple querystring parameters:


Filter list

The following filters can be used in all Field Testing endpoints:

date20230401-20230501The date range in yyyyMMdd-yyyyMMdd format. Defaults to last 90 days
regioneurope / us / dkA two-letter country code or a region name (eu, europe, latam, apac, emea, north_america, americas, oceania, asia, africa)
devicedesktopdesktop, mobile or tablet (or a combination)
browserchrome+edgeBrowser type - chrome, edge, firefox, safari, opera, ie, android
osmac_osOperating system - windows, mac_os, linux, ios, android
page/productsOne or more pages to filter by
tagsemail_campaignOne or more custom tags set via the JS API
referrer_typeextReferrer type - none, self (internal link) or ext (external link)

Timing and percentile settings

Some Field Testing reports support setting the timing metrics and the percentile of the metrics:

p90The percentile used in the metric values. Can be 50(median), 75, 90, 95 and 99. Defaults to 75th.
timinglcp+fid+clsA list of the metrics to be used in the Field Testing reports*

*) Only supported in the Pages and Countries reports. Click on documentation for those reports to see the metric list.

Custom variables

If you have added custom variables to your website, you can also use them as filters. You can add both string variables and numeric variables, as described here.

String variables

A string variable (example: cache_state) can be used in filters like this:

Equalscache_state=coldMatches a single variable value
One ofcache_state=cold+warmMatches one of a list of values
Does not equalcache_state=~coldThe variable must not equal the value
None ofcache_state=~cold+warmThe variable must not match any of the values in the list
Is setcache_state=*The variable is set to any value
Is not setcache_state=~The variable is not set

Numeric variables

A numeric value (example: react_hydrate_time) can be used in filters like this:

Equalsreact_hydrate_time=100Matches an exact number
Greater thanreact_hydrate_time=100..The variable value is greater than the given value
Less thanreact_hydrate_time=..100The variable value is less than the given value
Betweenreact_hydrate_time=100..200The variable value is between the two given values
Is setreact_hydrate_time=*The variable is set to any value
Is not setreact_hydrate_time=~The variable is not set