Free sending domain generator.
Enter your brand and get sending domain names that read as you without being you. Your primary domain never sends cold email, because reputation damage has to be disposable. The reference below covers naming, TLDs and everything a new domain needs before its first send.
Privacy: this tool runs entirely in your browser. Nothing you type leaves this page, nothing is stored, and nothing is sent to GrowthPal.
Sending domains at a glance
| Item | Value |
|---|---|
| The rule | Your primary domain never sends cold email. Not once, not for a test |
| Why | Reputation damage has to be disposable. You can retire a sending domain; you cannot retire the one your invoices go out on |
| TLD | .com, and it is not close. Cheap TLDs carry the reputation of everything else sent from them |
| Inboxes per domain | Two or three, so one bad domain costs a slice of capacity rather than the campaign |
| Before the first send | Redirect to your real site, SPF, DKIM, DMARC, MX, and four to six weeks of warmup |
What is a sending domain?
A sending domain is a separate domain, registered by you and pointed at your real site, used only for outbound campaigns. It carries its own authentication, its own inboxes and its own reputation.
The separation exists because cold email at volume always carries reputation risk, however careful you are. A bad week on a sending domain is an inconvenience: you pause it, diagnose, and warm another. The same week on your primary domain means password resets, invoices, contracts and investor updates start landing in spam, and no campaign result is worth that.
The name matters more than people expect. A recipient sees the sender domain before they read a word, and a domain that reads as a random string does the opposite of what a signal-based campaign is trying to achieve. Close to your brand, obviously separate, and nothing that looks like a character-swap impersonation.
How to read the names this suggests
The generator combines your brand with prefixes and suffixes that read naturally, then flags the three things that decide whether a name is usable.
Close to brand is the first note. A recipient scanning an inbox row reads the domain as a claim about who you are, so it should be recognisably you rather than an unrelated string with your name buried in it.
Stick to .com and .co is the second. This is not aesthetics. Cheap TLDs are cheap because they attract bulk registration, and several are filtered close to on sight regardless of what you personally send from them.
Availability is the one the tool cannot answer, because checking registration needs a registrar lookup rather than a DNS query from a browser. Take the shortlist to your registrar.
It also points you at the inbox calculator, because how many domains you need is arithmetic rather than preference: contacts, touches, sends per inbox per day, inboxes per domain.
Naming patterns that work, and ones that do not
| Pattern | Example for acme.com | Verdict |
|---|---|---|
| Prefix | getacme.com, tryacme.com | Good. Reads as a product page, obviously related. |
| Suffix | acmehq.com, acme-team.com | Good. Clearly the same company. |
| Descriptive | acmesales.com, acmemail.com | Workable, though naming the function tells the recipient it is bulk. |
| Alternate TLD on the same word | acme.co | Good where available, and usually is not. |
| Character swap | acrne.com, acme-1.com | Avoid. This is the exact shape filters are trained to catch as phishing. |
| Unrelated string | bestreachnow.com | Avoid. Nothing connects it to you, so it earns no trust and builds none for the brand. |
| Cheap TLD | acme.xyz, acme.top | Avoid. You inherit the reputation of everyone else on it. |
What a domain needs before its first send
| Step | Why | When |
|---|---|---|
| Redirect or landing page | A domain with no web presence looks disposable, because it usually is. | At registration |
| SPF | Names the servers allowed to send as it. | Before any mailbox is created |
| DKIM | Signs each message so receivers can verify it was not altered. | Before any mailbox is created |
| DMARC | Ties the two to the visible From address and starts the reports. | Before any mailbox is created |
| MX | So replies, bounces and out-of-office messages have somewhere to land. | Before warmup |
| Age | A domain registered this morning sending cold mail stacks two negative signals at once. | Roughly two weeks before first send |
| Warmup | Builds the sending history that placement depends on. | Four to six weeks |
How to set up a sending domain from scratch
- Register the name, in .com. Buy the shortlist rather than one, because you will need more than you think and consistent naming is easier bought in one go.
- Point it somewhere real. A 301 to your primary site is enough. A small landing page is better.
- Publish SPF, DKIM and DMARC. All three before a mailbox exists, so no message ever leaves unauthenticated.
- Publish MX records for wherever replies should land, then send a test message to the domain and confirm it arrives.
- Create two or three mailboxes, no more. This is a blast-radius decision, not a cost decision.
- Warm every mailbox for four to six weeks before it touches a campaign, then keep warmup running at reduced volume afterwards.
Common questions about sending domains
How different should a lookalike be from my real domain?
Close enough that a buyer reads it as you, far enough that it is plainly a separate domain. getacme.com or acme-hq.com for acme.com. Avoid character swaps and lookalike letters, because that is precisely the pattern filters are trained to catch as phishing.
What do these domains need besides the ability to send?
A redirect to your primary site or a real landing page, and full SPF, DKIM and DMARC published before the first warmup send. A domain with no web presence and no authentication has nothing vouching for it at the moment it needs vouching for most.
How old should a domain be before it sends?
Leave around two weeks between registration and the first send where you can, on top of warmup. Domain age is a weak signal by itself, but a brand new domain sending cold mail on day one stacks two negatives at the same time.
Does the TLD matter?
Yes, and .com is not a close call. Cheaper TLDs carry the accumulated reputation of everything else sent from them, and a few are filtered close to on sight. The ten dollars saved at registration is not worth the placement it costs.
How many sending domains do I actually need?
Work it backwards from volume rather than picking a number. Contacts times touches gives total sends, divided by roughly 30 sends per inbox per day gives inboxes, divided by two or three gives domains. Most plans underestimate this by about half, which is what the inbox calculator is for.
Can I reuse a domain that had a bad month?
Sometimes, but rarely worth it. Retiring the domain and warming a fresh one usually costs less time than rehabilitating a damaged reputation, and that disposability is the entire reason for sending domains. Retire it, find what caused the bad month, and do not repeat it on the replacement.
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