A home valuation is an estimate of what your property is worth. There is no single "official" number that everyone agrees on — instead, there are a few different ways to arrive at a value, each built for a different purpose. The three most common are an AVM (automated valuation model), a professional appraisal, and a CMA (comparative market analysis). Understanding what each one is, and when it's used, helps you read the number you see and know when to look deeper.
AVM (automated valuation model). An AVM is a software estimate. It calculates a value automatically from public records, tax data, and recent sales of comparable homes nearby. Because it runs on data, it can produce a number instantly and update frequently. It does not involve a person visiting the home. The value you see in an online home-value tool or in your Portfolio dashboard is typically an AVM.
Professional appraisal. An appraisal is an opinion of value produced by a licensed appraiser who inspects the home in person. The appraiser looks at the property's condition, size, layout, and features, then compares it to recent sales of similar homes and makes adjustments for differences. Appraisals follow professional standards and are usually required by a lender before a mortgage, refinance, or home-equity loan closes.
CMA (comparative market analysis). A CMA is a pricing estimate prepared by a real estate agent, usually when you're getting ready to list a home for sale. The agent selects recent comparable sales, factors in current market conditions and your home's specific features, and recommends a price or price range. A CMA blends data with local market judgment.
Put simply:
The biggest difference among the three is who (or what) produces the number and whether anyone sees the inside of the home. An AVM works only from the data it can access, so it generally cannot account for interior condition, recent renovations, or unusual features. An appraisal and a CMA both involve a human who can observe those things.
Because they use different inputs and methods, these estimates can differ meaningfully from one another — that's expected, not a mistake. An AVM is a strong starting point for understanding your home's value and watching it change month to month. When money is on the line — a sale, a mortgage, or a home-equity decision — a professional appraisal or a CMA gives a more tailored view.
One thing you can control across all three: the quality of your home's facts. Accurate, up-to-date details — beds, baths, square footage, condition, and renovations — improve the estimate. If your home's data is outdated, correcting it helps.
There are three common ways to value a home — an automated AVM, a licensed appraisal, and an agent's CMA — and each serves a different purpose. An AVM is best for a fast, ongoing estimate; an appraisal is the standard for lending; a CMA supports pricing a home for sale. Knowing which one you're looking at, and its limits, helps you use the number wisely.