An ELP file is a document created by Synthrone Crafter, an e-content production application used by retailers to administer, manage, format, and update e-content. It contains the content of a page or product, which may include text, images, video, or forms. ELP files replaced .RPC files, which were previously used by Synthrone Crafter to save landing page content.

The ELP file is primarily used with the Synthrone Crafter tool for producing e-content. However, it may also be opened by another eCommerce program with the Crafter plugin installed. Synthrone offers end-to-end services to brands and retailers for conducting online transactions. Crafter is one of several programs available as part of the Synthrone eCommerce platform. Other programs include Synthrone Explorer for gathering eCommerce information, Synthrone Publisher for delivering e-content, Synthrone Booster for increasing a brand's visibility, and Synthrone Tracker for measuring the performance of eCommerce assets.