A personal health record (PHR) is a health record where health data and other information related to the care of a patient is maintained by the patient. This stands in contrast to the more widely used electronic medical record (EMR), which is operated by institutions (such as hospitals) and contains data entered by clinicians (such as billing data) to support insurance claims. A PHR is intended to provide a complete and accurate summary of an individual's medical history that is accessible online. The health data on a PHR might include patient-reported outcome data, lab results, and data from devices such as wireless electronic weighing scales or (collected passively) from a smartphone.

The term "personal health record" was used as early as June 1978, and, in 1956, there was a reference was made to a "personal health log." The term "PHR" may be applied to both paper-based and computerized systems; usage in the late 2010s usually implies an electronic application used to collect and store health data.

In the early 2000s, healthcare organizations began to propose formal definitions of the term. For example:

The Personal Health Record (PHR) is an Internet-based set of tools that allows people to access and coordinate their lifelong health information and make appropriate parts of it available to those who need it. PHRs offer an integrated and comprehensive view of health information, including information people generate themselves such as symptoms and medication use, information from doctors such as diagnoses and test results, and information from their pharmacies and insurance companies.

— Markle Foundation's Personal Health Working Group, Connecting for Health (2003)

The personal health record (PHR) is an electronic, universally available, lifelong resource of health information needed by individuals to make health decisions. Individuals own and manage the information in the PHR, which comes from healthcare providers and the individual. The PHR is maintained in a secure and private environment, with the individual determining rights of access. The PHR is separate from and does not replace the legal record of any provider.

— AHIMA e-HIM Personal Health Record Work Group (2005)

The industry model personal health record (PHR) is a private, secure web-based tool maintained by an insurer that contains claims and administrative information. PHRs may also include information that is entered by consumers themselves, as well as data from other sources such as pharmacies, labs, and care providers. PHRs enable individual patients and their designated caregivers to view and manage health information and play a greater role in their own health care.