Somewhere out there is a homeowner refreshing Zillow at midnight like it's going to text back. If that's you: relax, put the phone down, and let's talk about what that number actually means — and why it might be quietly lying to you.
"What's my home worth" is one of the most-searched real estate questions there is, right up there with "how much house can I afford." Which makes sense — for most people, their home is the single largest asset they own, and checking its value has basically become a national pastime, somewhere between checking the weather and doom-scrolling your ex's Instagram.
So let's actually answer it — starting with the automated tools everyone checks first, and why the number you see isn't always the number your home would actually sell for.
How Accurate Is Zillow's Zestimate, Really?
Here's the honest version, not the marketing version: Zillow reports a median error rate of roughly 1.9-2.4% for homes currently listed for sale, and around 7% for homes that aren't on the market — which, if your home isn't currently listed, is the number that actually applies to you.
Here's the part Zillow doesn't advertise as loudly: the "on-market" accuracy looks great mainly because the algorithm gets to see the actual list price and essentially anchors to it. It's not predicting — it's copying the agent's homework, then rounding. The off-market number is the real test of the algorithm's skill, and that's where the 7% shows up.
A 7% median error doesn't sound dramatic until you put a real number on it: on a $750,000 home, that's a potential swing of over $52,000 — in either direction. And remember, "median" means half of all estimates are more off than that, not less.
How Accurate Is Redfin's Estimate?
Redfin's numbers land in almost the same neighborhood: roughly 2-3% median error for on-market homes, and somewhere between 6.5-8.7% for off-market homes, depending on which report you read. The two companies go back and forth on which is marginally better, but the honest takeaway is: it's a wash. Neither one has cracked the code on knowing what your home is worth without seeing inside it.
Redfin does have one real advantage worth naming: it shows you the comparable properties it used to build the estimate, so you can actually see its work. Zillow mostly just hands you a number and asks you to trust it, which — respectfully — is not how I'd want my largest financial asset valued.
So Why Are They Off By So Much?
Because neither tool has ever walked through your house. An algorithm can pull square footage, bedroom count, and public tax records — but it has no idea that you:
Renovated the kitchen last year (or haven't touched it since 1997)
Have a finished basement that isn't reflected in county records
Live next to the neighbor whose yard has become a small automotive museum
Back up to a greenbelt instead of another rooftop
Have foundation issues nobody's disclosed yet, or a view that adds real premium
These tools are pattern-matching machines working off public data. They're a reasonable starting point for "am I in the right ballpark," and a genuinely bad tool for "what should I actually list this for" or "what's a fair offer."
What Actually Determines Your Home's Real Value
Recent comparable sales — not list prices, actual closed sales, adjusted for differences in size, condition, and lot.
Condition and updates — the kitchen, the roof, the HVAC system's age, whether the bathroom was renovated in this decade or the one your parents remember fondly.
Micro-location — not just "which city," but which street, which side of the street, and whether you're three minutes or thirteen minutes from the nearest good coffee.
Current market conditions — inventory levels, buyer demand, and interest rates all move the number in ways a six-month-old algorithm snapshot won't capture.
Things no database tracks — natural light, layout flow, whether the primary bedroom is a genuine retreat or technically just "the biggest room with a door."
The Real Answer: Get an Actual CMA
A Comparative Market Analysis (CMA) from a local agent isn't a guess dressed up in a nicer font — it's a human being who knows your specific market pulling truly comparable recent sales, adjusting for your home's actual condition and features, and walking the property in person. It costs you nothing, and it's meaningfully more accurate than anyAVM (automated valuation model), because it accounts for the things a database structurally cannot see.
If you want the quick gut-check, Zillow and Redfin are fine for "am I roughly in the right zip code of value." If you're making an actual decision — selling, refinancing, or just genuinely curious what you're sitting on — a real CMA is the difference between a guess and an answer.
Curious what your home is actually worth — not the algorithm's best guess? I'll walk your property and pull real comparable sales specific to your street, not just your zip code. Get your free home valuation and let's find your real number.
— Lerryn McCullough, MLG Partners
