A mistyped address is a lost reply

When you make an offer here, the reply goes to the address you typed. If a letter slipped, nothing bounces back to you — the offer is recorded, the seller answers it, and the answer goes nowhere. From your side that looks exactly like being ignored.

Three checks now stand between a slip and a silence. Two of them you will never see.

The letter that slipped

Type an address at a domain that is one or two keystrokes away from a provider you almost certainly meant, and the field offers the correction underneath it:

Did you mean you@gmail.com?

Click it and the address is replaced. Ignore it and nothing happens — the address you typed is the address that is used. That is deliberate: a name that merely resembles a large provider is sometimes exactly right, and a form that quietly rewrote it would be worse than one that said nothing. The suggestion is a question, never a correction applied on your behalf.

The check knows the spelling of the large consumer providers, including the ones a keystroke apart from each other. It says nothing about a company domain, because a company domain that does not resemble Gmail is not evidence of anything.

The domain that cannot receive mail

The second check is quieter and does not appear unless something is wrong. Before the form is accepted, we ask the public directory whether the domain part of your address can receive mail at all. A domain that does not exist is refused, with a message naming which of the addresses to look at, rather than accepted into a silence.

There is a subtlety worth stating, because it is the reason the first check exists at all. Misspellings of famous providers are usually registered on purpose by someone hoping to catch exactly this mistake. They resolve. They have web servers. Asking the directory about them yields an answer that looks entirely healthy — which is why a spelling suggestion, and not a lookup, is what catches them. Conversely, a domain that is pure keyboard mash does not exist at all, and no amount of spelling knowledge helps there; the lookup catches those. Each check covers the other's blind spot.

The domain that resolves but was never a mailbox

Between those two there was still a gap, and it took a third check to close. A domain can be registered, resolve perfectly, and serve a page, and still have never been set up to receive mail. There is nothing for a spelling suggestion to propose and nothing for the directory to object to.

What separates the two cases turns out to be simple. A domain that seriously accepts mail publishes a mail server — a record that says send mail for this domain here. Real providers all publish one. The parked domains and the throwaway registrations do not; they have a web address and nothing else, and mail sent to them is delivered on a technicality left over from the 1980s.

So when — and only when — the domain in your address publishes no mail server at all, the offer form asks you to confirm the address before the offer is sent. We email a six-digit code and the page asks you to type it back. Until you do, the offer has not been sent: it is not recorded, and the seller is not told about it.

If you use Gmail, iCloud, Outlook, or a company address, you will never see this. Every one of them publishes a mail server, and we checked the addresses this site has actually collected: not one of them would have been asked. The step exists for the shape of address that has never once belonged to a real buyer.

The code is good for half an hour. If it does not arrive, the address almost certainly cannot receive mail, which is the thing we were trying to find out.

What this does not claim

It does not verify that your mailbox exists. Nothing outside your mail provider can, and any service promising otherwise is guessing — the large providers stopped answering that question years ago, precisely because it was being used to harvest addresses. We check that a domain can receive mail, not that a person is behind it.

So an address that is well-formed, at a real provider, and simply not yours will still be accepted — the confirmation step above applies only to domains with no mail server, which real providers are not. If you are waiting on a reply and it has not come, the likeliest explanation is still a wrong address, and the fastest fix is to make the offer again with the right one.

Nobody new receives your address

We considered the usual commercial email-verification services and did not use one. Every one of them works by receiving the address you typed.

The spelling check runs entirely in your browser: the comparison list ships with the page, and your address is never transmitted anywhere to produce that suggestion.

The second check is a directory lookup, and it asks about the domain part only — the piece after the @, which is public information about a mail host, shared by everyone who uses it. The part that identifies you is never in that question. To be exact rather than flattering: the lookup goes to Cloudflare's public resolver, and Cloudflare already serves this site, so it is not a new party to your visit. What has not been added is a verification vendor — nobody new receives your address in order to tell us whether it looks real.

The confirmation code is the one message this sends, it goes to you and nowhere else, and it carries no tracking of any kind — no pixel, no rewritten links. If a code reaches you and you did not make an offer, you can ignore it: nothing was recorded and nothing reached a seller.

Updated 8 September 2026: the third check — the confirmation code for domains that publish no mail server — was added the day after this post first went up. The two checks above are unchanged, and the section on what is sent where has been rewritten to account for the code, which is now the one message this site sends as a result of the address you type.