ReportingObserver: ReportingObserver() constructor
Baseline
2026
*
Newly available
Since March 2026, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.
* Some parts of this feature may have varying levels of support.
Note: This feature is available in Web Workers.
The ReportingObserver() constructor of the Reporting API creates a new ReportingObserver object instance, which can be used to collect and access reports.
Syntax
new ReportingObserver(callback)
new ReportingObserver(callback, options)
Parameters
callback-
A callback function that runs when the observer starts to collect reports (i.e., via
ReportingObserver.observe()). The callback function is given two parameters:reports-
A sequence of objects representing the reports collected in the observer's report queue.
Report objects are expected to have the following properties:
body-
An object representing the body of the report. The structure of the report (in particular of its body), depends on its
type. type-
A string indicating the type of the report. For information on report types see
options.typesbelow. url-
A string representing the URL of the document that generated the report.
observer-
A reference to the same
ReportingObserverobject, allowing for recursive report collection, and so on.
optionsOptional-
An object allowing you to set the options for creating the object. The available options are:
types-
An array of strings representing the types of report to be collected by this observer. Available types include:
coep-
Violations of the site's
Cross-Origin-Embedder-Policy(COEP). Reports areCOEPViolationReportinstances. crash-
Browser crash reports. (crash reports aren't retrievable via a
ReportingObserverbut can be sent to a server). csp-violation-
Violations of the site's CSP policy. Reports are
CSPViolationReportinstances. deprecation-
Deprecated features used by the site. Reports are
DeprecationReportinstances. integrity-violation-
Violations of the page's integrity policy. Reports are
IntegrityViolationReportinstances. intervention-
Features blocked by the user agent, for example, if an ad significantly impacts page performance. Reports are
InterventionReportinstances.
If this option is omitted, all supported types are collected.
buffered-
A boolean that defines whether the reports that were generated before the observer was able to be created should be observable (
true) or not (false).
Examples
Display specific report types
This code shows how to create a ReportingObserver that could be used to observe deprecation and integrity-violation reports.
const options = {
types: ["deprecation", "integrity-violation"],
buffered: true,
};
const observer = new ReportingObserver((reports, observer) => {
reportBtn.onclick = () => displayReports(reports);
}, options);
Specifications
| Specification |
|---|
| Reporting API # dom-reportingobserver-reportingobserver |