Traditional metric tools are authoritative and widely recognized. These are found in sources such as Web of Science and Journal Citation Reports--these and more are accessible from this page--and include metrics such as the h-index and journal impact factor. For broader impact, consider incorporating these tools with altmetric tools.
Use these for basic counts of the number of times an article has been cited.
Use these tools to generate data by author for activity such as promotion & tenure review and candidate searches.
Use these to obtain data by journal, such as impact factor and h-index.