Real estate appraisal, property valuation or land valuation is the process of developing an opinion of value for real property (usually market value). Real estate transactions often require appraisals because they occur infrequently and every property is unique (especially their condition, a key factor in valuation), unlike corporate stocks, which are traded daily and are identical (thus a centralized Walrasian auction like a stock exchange is unrealistic). The location also plays a key role in valuation. However, since property cannot change location, it is often the upgrades or improvements to the home that can change its value. Appraisal reports form the basis for mortgage loans, settling estates and divorces, taxation, and so on. Sometimes an appraisal report is used to establish a sale price for a property.

Besides the mandatory educational grade, which can vary from Finance to Construction Technology, most, but not all, countries require appraisers to have the license for the practice. Usually, the real estate appraiser has the opportunity to reach 3 levels of certification: Appraisal Trainee, Licensed Appraiser and Certified Appraiser. The second and third levels of license require no less than 2000 experience hours in 12 months and 2500 experience hours in no less than 24 months respectively. Appraisers are often known as "property valuers" or "land valuers"; in British English they are "valuation surveyors". If the appraiser's opinion is based on market value, then it must also be based on the highest and best use of the real property. In the United States, mortgage valuations of improved residential properties are generally reported on a standardized form like the Uniform Residential Appraisal Report. Appraisals of more commercial properties (e.g., income-producing, raw land) are often reported in narrative format and completed by a Certified General Appraiser.