The short answer
Automated domain appraisals are reasonably good at ranking names against each other and poor at predicting what any single name will sell for. That distinction is the whole story. If a tool tells you one name is worth more than another it is usually right; if it tells you a name is worth $4,200 it is telling you about a distribution, not about your name.
Free appraisal tools at a glance
Most free appraisal tools return a single number, but they are built on different data and report different things. This is what each one gives you and where its figure comes from.
| Tool | What you get | Built on | Notes |
|---|---|---|---|
| GoDaddy | One estimated value | GoDaddy’s own aftermarket sales | Registrar-run. The most widely used, and the one sellers most often say overshoots real offers. |
| Atom | Estimate plus market insights | AI over hundreds of data points, including sell-through rates and comparable sales | Marketplace-run. |
| HumbleWorth | Separate auction, marketplace and brokerage estimates | Reported sales data | No account, no daily limit. Bulk checks up to 2,000 names. |
| Dynadot | One instant estimate | Length, keyword demand, extension and aftermarket sales | Registrar-run. |
| Estibot | Estimate with keyword metrics | Search volume, advertising cost and recorded sales | Strongest on descriptive keyword names, weakest on brandables. |
| NameWorth | Appraisal with market stats | Market data aimed at domain investors | Often listed alongside GoDaddy and Estibot as a standard tool. |
| pc.domains | One estimated value | Machine learning on 2.6M+ recorded sales | Free tier with paid plans. |
| SiteAppraiser | Quick-sale and retail figures, every factor scored | Name structure, extension, length and niche demand | No signup or email. |
| NameBio | Not an appraiser: a sales lookup | $3B+ of recorded domain sales | Use it to check any estimate against what similar names actually sold for. |
For one name, run at least three tools built on different data, such as a registrar tool, HumbleWorth and Estibot. Then look up similar names on NameBio before you set a price. SiteAppraiser’s checker shows each factor behind its estimate, so you can see why it differs from the others.
They are not all answering the same question
Before comparing outputs it is worth noticing that these tools are not estimating the same thing. One may be estimating aftermarket resale value — what another investor would pay. Another may be estimating end-user value — what a business that wants the name would pay. A third may be estimating what the name would realistically fetch inside that marketplace. Three different quantities, reported in the same units, which is why the numbers look comparable when they are not.
What each is built on
Broadly, appraisal engines draw on three kinds of input: recorded aftermarket sales, keyword and search data such as volume and advertising cost, and structural features of the name itself — length, extension, dictionary-word status, hyphens and numbers. The mix decides where an engine is strong. Sales-weighted models are strongest where sales are dense; keyword models are strongest on descriptive commercial names; structural models degrade gracefully everywhere and excel nowhere.
Registrar and marketplace tools
An appraisal offered by a registrar or marketplace sits inside a business that wants you to transact. That is not a reason to dismiss the number — access to proprietary sales data is a genuine advantage that independent tools do not have. It is a reason to read it in context. The incentive does not point toward conservative estimates, and a high appraisal makes listing, renewing and buying all feel more rational than they might be.
Keyword-driven tools
Tools built primarily on search and advertising data are strongest on descriptive, commercial names — the sort of phrase a business would target in paid search. Where a name maps cleanly to a keyword with real advertising spend behind it, the estimate has something solid underneath. Where it does not — an invented brandable, an acronym — the model is extrapolating from a signal that does not exist for your name.
The category where they work
Automated valuation is most reliable on names with dense comparable data: short dictionary words, common two-word combinations, and names in extensions with high sales volume. There are thousands of recorded transactions in these categories, the distribution is tight, and an estimate lands inside a defensible range.
The category where they fail
Accuracy collapses on invented brandables, very short acronyms, and new extensions. A five-letter coined name has almost no true comparables — the sales that exist range from $200 to six figures depending entirely on whether a funded company happened to want that exact word. No model can predict that, and the ones that try produce confident numbers with nothing behind them.
Automated appraisals are systematically optimistic
The consistent complaint from people who have actually tried to sell is that the appraisal was higher than any offer received. Some of this is selection bias in what gets complained about, but there is a real mechanism underneath: the models are trained on sales that completed. Names that never sold at any price are absent from the training data entirely, so the estimate reflects the distribution of successful sales rather than the distribution of all names.
Reading agreement and disagreement
Agreement between tools is the most useful signal any of them produce. If three engines built on different data land within a narrow band, the name has dense comparable sales and the range is real. A wide spread — where low and high differ by a factor of ten — is not a sign that one tool is broken. It means the name sits in a category with sparse or highly variable comparable data, which is itself the finding. Run the name through each, record the low, high and spread, and ignore the average: averaging three estimates of different quantities produces a number that measures nothing. Read the low as a plausible floor and the high as a ceiling conditional on the right end user appearing.
What a number cannot include
No automated appraisal knows whether your name has a trademark conflict, whether it was previously used for spam, whether it carries an unfortunate reading in another language, or whether a similar name in the same space just sold and reset expectations. These are the things that most often turn a plausible price into an unsellable one, and none of them are in the data.
Do any of them tell you whether it will sell?
No, and this is the question most owners actually have. All of these tools estimate value in the abstract, not liquidity. Whether a name sells depends on whether it is discoverable, whether the price is actionable, and whether a matching buyer is looking right now — questions answered by listing it, not by running another appraisal.
When an appraisal is worth paying for
Paid manual appraisals from brokers are a different product from an automated estimate: a person with transaction experience looks at the name, the extension, the likely buyer pool and the comparable sales, and gives you a defensible figure. Worth it when a real decision depends on the number — a purchase above a few thousand dollars, a partner buyout, a tax or insurance valuation. Not worth it for a routine renewal decision.
| Service | What you get | Price |
|---|---|---|
| Sedo | Independent expert review | From $99 |
| Saw.com | Valuation by a broker using comparable sales and market data | Quote on request |
| MediaOptions | Broker appraisal drawing on niche experts | Quote on request |
Prices as published by each provider in October 2026. Confirm before ordering.
What to do with the number you have
Use the appraisal to decide which of your names deserve effort, which is what it is genuinely good for. Then price against comparable sales rather than against the appraisal, list somewhere with real buyer traffic, and let the market correct you. The estimate is a starting hypothesis, not evidence. For the venues with the most buyers and what each charges, see where to sell domain names.
- Appraisal tools rank names well and predict individual prices badly.
- They measure different things — reseller value, end-user value, marketplace value.
- A wide spread means the name has no real comparables; a tight cluster means it does.
- Do not average them. Read the low as a floor, the high as a conditional ceiling.
- Automated estimates read high — unsold names are missing from the training data.
- No tool sees trademark conflicts, spam history, or who the buyer would be.
Value the name itself — separate from any site on it, no email required. The method and the reported sales behind the estimate are published alongside it.
Appraise a domainNamecheap runs a domain marketplace alongside the registrar, so you can list a domain for sale, park it for ad revenue, or grab the next one cheaply.
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