公信力指对信息或其来源可信度的主观及客观组成。

传统意义上，公信力有两个基本要素：可信度和专业度，两者都由主观和客观组成。可信度更多地创建在主观因素基础上，但也包括客观衡量标准，如公认的可靠信息。专业度同样可被主观感知，同时也包括相关信息的客观的特征，如凭证、证书和信息质量等。公信力的次要要素包括信息来源的活力和吸引力。

1990年代中期开始，网络已成为一个重要的信息源，网络公信力也因此成为一个重要的研究课题。加州大学圣巴巴拉分校公信力和数字媒体工程正进行此方面的研究，并将其列为近期研究重点。研究内容包括数字媒体、青年人和公信力。此外，斯坦福大学的科技说服者实验室也已展开网络公信力的研究，并提出网络公信力的主要组成和概述性理论--显释论。

Credibility refers to the objective and subjective components of the believability of a source or message.

Traditionally, modern, credibility, reliability has two key components: trustworthiness and expertise, which both have objective and subjective components. Trustworthiness is based more on subjective factors, but can include objective measurements such as established reliability. Expertise can be similarly subjectively perceived, but also includes relatively objective characteristics of the source or message (e.g., credentials, certification or information quality). Secondary components of credibility include source dynamism (charisma) and physical attractiveness.