dot·sweep

dotsweep vs Vercel Domains Registrar API

A registrar API inside the platform the caller is probably already deploying to, covering availability, pricing, purchase, transfer, renewal and nameservers.

dotsweepVercel Domains Registrar API
No key YesNo key, no account, no signup. curl https://dotsweep.com/check/example.com works from a cold start. NoA bearer token from a Vercel account. The documented failures include a 403 not_authorized_for_scope, so the token also has to be scoped to the team that owns the domain.
Admits doubt YesA registry that is throttled, timed out or publishes no RDAP resolves to estimated, never available. A 429 from one registry does not become a confident answer about another one on the same host. NoTheir published response schema for the availability endpoint has one property, available, typed boolean and listed as required. There is no third value and no confidence field, so a registry that could not be reached has nowhere to be reported except as one of the two answers or an error.
Renewal + term YesRegistration and renewal are separate figures, a first-year discount is flagged as a promotion, and an extension the registry sells only in multi-year terms is multiplied out so the leading number is what leaves your account. YesThe price endpoint returns purchasePrice, renewalPrice and transferPrice, all required, alongside years. The years parameter is documented as "If not provided, the minimum number of years for the TLD will be used", so the minimum term is handled rather than left to the caller.
Eligibility Partly38 extensions have had their registry policy read, 33 of them with an eligibility rule, each citing the registry's own page and the date it was read. An extension that is not in that set asserts nothing. Not documentedThey document a contact-schema endpoint for TLD-specific contact requirements, which is adjacent to this question without answering it. We found no field saying who is permitted to register a name.
Free tier Yes120 requests a minute, counted as requests rather than domains, and a batch endpoint carrying 10 domains each. No daily or monthly ceiling and no credit balance, so the rate is the whole quota. Edge cache hits are not counted at all. Not documentedTheir reference documents a 429 carrying a limit object with total, remaining and reset, so a ceiling exists. The pages we read do not give its value or say what it costs.
Assistant-ready YesA remote MCP server at /mcp over the same handlers, addable as one URL with no account and no key, plus /llms.txt so an assistant that only fetches can still call it. Not documentedWe found no MCP server or assistant-facing interface for the registrar endpoints on the pages we read, and we did not test one.

Where Vercel Domains Registrar API is the better choice

Written first because a comparison written by one of the two products is worth nothing if it cannot say this.

Where dotsweep is different

The unconfirmed-rather-than-available rule is the one worth explaining, because it is the only wrong answer in this category that costs somebody money. A registry that is rate-limiting you often phrases the refusal in words a parser reads as "no such domain", so the naive result of a throttled lookup is a confident "available" for a name somebody already owns. dotsweep asserts this in its test suite in both engines, and marks the answer estimated instead.

Is dotsweep better than Vercel Domains Registrar API?

Not at everything, and not for every job. Vercel Domains Registrar API does this better: Registration, renewal and transfer prices come from the registrar that will actually sell you the name, with an explicit term, so the quote and the checkout cannot disagree. Ours comes from a wholesale feed. dotsweep answers a different question: it needs no key or account, it returns the renewal price and the minimum term rather than the advertised first-year figure, it says who is allowed to register the extension, and it reports a throttled or unreachable registry as unconfirmed rather than available.

What Vercel Domains Registrar API documents

How we know this, and what we did not do

Every claim about another product here was read from that vendor's own documentation, and each one is listed with the page and the date it was read. No figure comes from a review, a listicle or another comparison.

We did not benchmark any of these services. Nothing on this page reports a measurement, and where a row says "not documented" it means their documentation did not answer the question and we did not test it. It is not a quiet way of saying no. Getting that distinction wrong is how the rest of a comparison table stops being worth reading, and it is the same rule the rest of this site follows about extensions whose registry policy nobody has read.

If something here is out of date or wrong, the date next to it is there so you can tell which, and support@dotsweep.com reaches a person.

The one claim here that is measured rather than cited

Every row above comes from a vendor's own documentation. One thing does not, because no vendor documents it: what a checker concludes when the registry refuses to answer. That is testable, and the test is published with its method and a way to run it against your own — including why the obvious version of the experiment, waiting for a real rate limit and asking everyone at once, cannot work.

Check a name without signing up for anything

curl https://dotsweep.com/check/example.com

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