Do Diffbot APIs execute Javascript?

Diffbot Automatic APIs execute page-level Javascript at render-time, and for the most part will be able to access Ajax-delivered content. Note that while creating a custom API you will not be able to preview Javascript-delivered content (see related support article), but it will be accessible when making actual API calls.

Versions 1 and 2 of the Article API do not execute Javascript.

Crawlbot does not execute Javascript when harvesting/collecting links by default, but it can be modified to do so while using the Analyze API. See How to find and access Ajax-generated links while crawling for details on enabling this functionality.

Service Executes Javascript?
Analyze API Always.
Article API Version 3 and above.
Discussion API Always.
Image API Always.
Product API Always.
Video API Always.
Custom APIs Always.
Crawlbot Always for processing pages. By default, not when collecting/harvesting links. See How to find and access Ajax-generated links while crawling.