This guide contains the answers to some commonly-asked questions about setting up, using and troubleshooting the JavaScript SDK.

Should I disable adblockers on my browser?

Yes, it is important to ensure that no ad blockers are running on your browser, as they restrict the JavaScript SDK script from executing and storing user information in the browser.

Can I load multiple instances of RudderStack JavaScript SDK?

No, it is not possible to load multiple instances of the JavaScript SDK, as it is bound to exceed the maximum stack call size and give you an error.

How can I verify if the SDK sends the data to the desired destinations?

To verify if the SDK is transmitting the events to the specified destinations, go to the Network tab of the JavaScript console in your browser.

Sample page call Sample track call

If you cannot see any outbound requests, verify if you have installed and set up the JavaScript SDK correctly. Also, check if any adblockers are enabled on your browser.

What is the size limit on the requests?

The event size limit on the requests is 32 KB per message and 4 MB per batch request.

Can I send the event data to specific destinations only?

Yes, you can send your event data only to the specific destinations by stopping the SDK from loading the other device mode integrations.

What is the "Reserved Keyword" error?

When using the JavaScript SDK, you may run into the following error:

Warning! : Reserved keyword used in traits --> id with track call.

This is because one or more keys in your traits or properties object have the same value as a reserved keyword.

RudderStack reserves the following keywords as keys for a standard event payload, and you should avoid using these while naming your event traits and properties:


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