Knowing how to check email domain reputation is the difference between watching a slow slide into the spam folder and finding out after replies flatline. Reputation is not guesswork: Google and Microsoft both publish free dashboards that report how their systems see your sending, and reading them takes minutes once they are set up. This guide covers the ten-minute Google Postmaster Tools setup, the dashboards that actually predict placement now that Google has retired its old reputation graph, the secondary checks worth adding, and the triage order when the readings dip.
We check these dashboards for a living. Our parent agency, Referral Program Pros, has run more than 4,000 outbound campaigns and booked over 7,000 meetings, and GTM Bud is built on that same playbook, backed by a guarantee of 5 percent positive replies on LinkedIn or 1.5 percent on email, or a full refund. A guarantee like that only survives if domain reputation is monitored before it becomes a problem, not diagnosed after.
One scope note first. This article is about reading your reputation. If your symptom is sudden hard bounces naming Spamhaus or another list, that is a blacklisting, a different diagnosis with its own sequence in our guide to checking and fixing a blacklisted email domain. Pre-send placement testing with seed inboxes lives in our guide to testing email deliverability, and the full infrastructure stack is in the cold email deliverability guide.
What is email domain reputation?
Email domain reputation is the score a mailbox provider assigns to your sending domain based on how its users and systems have treated your past mail: spam complaints, engagement, bounce behavior, authentication results, and spam-trap hits. It is first-party and private. Gmail keeps its own score, Microsoft keeps its own, Yahoo keeps its own, and none of them share a number with the others or fully disclose one to you. That is why “checking” reputation means reading the partial views each provider chooses to publish, then triangulating. It is also why reputation differs per provider: the same domain can place fine at Outlook while Gmail junks it. The domain is the asset that carries this history from campaign to campaign, which is exactly why burned domains get retired and why cold outreach should never run on the domain your invoices depend on.
Domain reputation vs blacklisting: two different diagnoses
Low reputation and a blocklist listing get conflated constantly, and the fix for one does nothing for the other. A blocklisting is public, binary, and externally checkable: an operator like Spamhaus added your domain or IP to a list, receiving servers that query the list refuse or junk your mail, and a free lookup tells you yes or no in seconds. Low reputation is private, gradual, and internal to each provider: nothing rejects your mail outright, placement just degrades as Gmail’s or Microsoft’s own scoring downgrades you.
The symptoms differ too. Listings tend to announce themselves with bounce codes that name the list. Reputation decay is silent: delivery “succeeds” while messages land in spam. If you see rejection bounces, run the delisting sequence in our blacklist check and fix guide first. If mail is delivered but ignored, you are in this article’s territory. A domain can also suffer both at once, in which case delist first, because a listed domain will keep bleeding reputation until the block clears.
Step 1: Set up Google Postmaster Tools in ten minutes
Google Postmaster Tools is the only dashboard where Gmail itself reports on your sending, and it is free. Setup is a one-time TXT-record verification per domain:
- Sign in at postmaster.google.com with any Google or Google Workspace account.
- Add your domain. Use the domain that authenticates your mail, without https or www. Add the root domain: per Google’s setup documentation, verifying the root gives you data for the root and its subdomains.
- Copy the verification record. Google shows a TXT record (a CNAME option exists too) unique to your domain.
- Publish it in DNS. In your DNS provider, add the TXT record at the root host, usually written as @ or left blank.
- Click Verify. DNS changes can take time to propagate, so a failed first attempt usually just means wait and retry.
- Repeat for every sending domain. Each secondary and lookalike domain in your fleet gets its own verification, on day one, before it carries volume. The dashboards need history to be useful, and history only accrues after verification.
That is the whole setup. The reading is where senders go wrong, partly because what you are reading changed in 2025.
Step 2: Read the dashboards that predict placement
If you last looked at Postmaster Tools before late 2025, recalibrate: the famous domain reputation graph with its High, Medium, Low, and Bad ratings no longer exists. Google retired the original Postmaster Tools on September 30, 2025, redirecting all users to Postmaster Tools v2, and the domain reputation and IP reputation dashboards were removed rather than migrated, per Google’s deprecation notice as covered by deliverability vendors including Folderly and InboxAlly. What remains, and what v2 added, is arguably more actionable. Three surfaces predict placement now:
- Spam rate. The percentage of your inbox-delivered mail that Gmail users manually mark as spam. This is the single most predictive number you can see. Google’s email sender guidelines set the bar every cold sender should treat as law: keep the spam rate below 0.3 percent, and ideally under 0.1 percent. Between those two numbers, filtering pressure builds; at 0.3 percent, enforcement starts. The thresholds and their enforcement are covered in depth in our guide to the Google and Yahoo bulk sender rules.
- Compliance status. New in v2, this dashboard grades your domain against Gmail’s sender requirements line by line: SPF, DKIM, and DMARC authentication, spam rate, one-click unsubscribe, and related items, each marked Compliant, Needs work, or No data found, per coverage of the v2 rollout from Suped and Blueshift. It converts “reputation” from a vague score into a checklist, and any Needs work row is your next task.
- Authentication. Tracks SPF, DKIM, and DMARC pass rates on your traffic. Healthy senders sit at effectively full pass rates; anything sagging here means some share of your mail looks forgeable, and the fix lives in our SPF, DKIM, and DMARC setup guide. Delivery errors, encryption, and feedback loop dashboards carried over from v1 and round out the picture.
The honest caveat for cold senders is sample size. At 20 to 30 sends per day per mailbox, the daily volume reaching personal Gmail accounts is often too small for the dashboards to report anything, so small senders frequently see No data. That does not make setup pointless: verify every domain anyway, because the dashboards become your primary monitoring surface the moment volume justifies them, and they only have history if you set them up early.
Step 3: Add Microsoft SNDS for the Outlook side
Microsoft’s equivalent is Smart Network Data Services, a free portal reporting how Microsoft’s systems see your sending toward Outlook.com and Hotmail inboxes. The key structural difference: SNDS is organized around sending IPs, not domains. You register and authorize the IP addresses you send from, and SNDS reports complaint rates, filter results, and message volume per IP, per Microsoft’s portal documentation as summarized by Mailgun and Twilio. SNDS historically also reported spam-trap hits, but Microsoft announced that trap hit counts leave the data report as of July 22, 2026, citing protection of its anti-abuse systems.
The IP-based design creates an honest limitation for most cold senders. If you send through Google Workspace or Microsoft 365, your mail leaves from provider-owned shared IP pools you cannot register, so SNDS has little to show you. It earns its place when you control dedicated sending infrastructure, and for everyone else the Outlook-side check falls back to seed testing: send your campaign message to your own Outlook.com account and see which folder it lands in, the manual pass detailed in our deliverability testing guide.
Step 4: Cross-check with third-party scores and seed tests
Third-party checks fill the gaps the provider dashboards leave, as long as you weight them correctly. Sender Score by Validity rates your sending IP from 0 to 100, built from complaint, trap, and volume data across Validity’s network and calculated on a rolling 30-day average, per Validity’s documentation. The free lookup requires a signup. Read it directionally: Gmail and Microsoft run their own first-party scoring and do not consult Validity’s number, so a strong Sender Score with a bad Postmaster Tools spam rate means you are in trouble, not the reverse. Seed placement tests are the other cross-check, an empirical reading of where your message actually lands today: GlockApps includes two free deliverability tests and ZeroBounce one free test per month, per each vendor’s site, and mail-tester scores authentication and content without a signup. The full free-first testing order is in our deliverability testing guide.
Here is how the surfaces compare:
| Check surface | What it actually tells you | Scope | Cost |
|---|---|---|---|
| Postmaster Tools v2 | Gmail’s own spam rate, compliance status, and authentication pass rates | Domain | Free |
| Microsoft SNDS | Microsoft’s per-IP complaint and filtering view for Outlook and Hotmail | Sending IP | Free, needs control of the IP |
| Sender Score (Validity) | Directional 0-100 third-party IP rating on a rolling 30-day average | Sending IP | Free lookup with signup |
| Seed placement test | Which folder a real message lands in today, per provider | Message + setup | Free tiers at GlockApps and ZeroBounce |
| Blocklist scan | Whether an operator has publicly listed your domain or IP | Domain and IP | Free via MxToolbox |
No single row is sufficient. The provider dashboards are authoritative but lag and need volume; seed tests are immediate but carry no history; Sender Score is continuous but secondhand. Checked together weekly, they catch reputation drift while it is still cheap to reverse.
The triage order when your reputation dips
A worsening reading has a diagnostic order, and running it backwards wastes weeks. Work down this list:
- Rule out a blacklisting. Run the domain and IP through a blocklist scan first, because a listing mimics reputation decay and nothing else improves until it clears. The delisting sequence is in our blacklist check and fix guide.
- Fix any authentication failure. A Needs work row on SPF, DKIM, or DMARC in the compliance dashboard outranks every other signal. Unauthenticated mail is filtered regardless of content or history.
- Attack the spam rate at its source: targeting. A climbing spam rate means recipients are reporting you, and the durable fix is a tighter audience and an easy opt-out, not better copy. The complaint math is unforgiving at cold volumes, where a single report on a low-volume day can spike the daily rate far past the 0.3 percent ceiling.
- Cut volume and re-warm. Treat a damaged domain like a new one: drop to warm-up levels and ramp back gradually while the dashboards recover, the process covered in our email warmup guide for cold outreach.
- Decide whether the domain is worth saving. A secondary domain that keeps relapsing is telling you its history is unrecoverable. At 10 to 15 dollars per year for a replacement, retirement is often the cheaper trade than rehabilitation.
The pattern across all five steps: reputation problems are behavior problems wearing a technical costume. Dashboards locate the damage; only changed sending behavior repairs it.
Frequently asked questions about checking email domain reputation
Can you check email domain reputation for free?
Yes, and the free surfaces are the ones that matter most. Google Postmaster Tools is free and is the only place Gmail reports its own view of your sending. Microsoft SNDS is free if you control your sending IPs, Validity offers a free Sender Score lookup with a signup, and MxToolbox runs a free blocklist scan. Paid monitoring mostly repackages these sources, so exhaust the free stack first.
How long does it take to repair a damaged domain reputation?
Plan in weeks, not days. A previously flagged domain often needs six to eight weeks of recovery warm-up, against two to four weeks for a brand-new one, based on the recovery ramps our agency runs and the practices in our email warmup guide. Reputation decays on the providers’ schedule, not yours, so for a cheap secondary domain the honest alternative is retiring it and warming a replacement.
Do subdomains share reputation with the root domain?
They are related but not identical. Verifying the root domain in Postmaster Tools gives you data for the root and its subdomains, per Google’s setup documentation. For the bulk sender rules, Google counts volume per primary domain, so subdomain mail rolls up into the same 5,000-per-day threshold as the root, per Google’s sender guidelines FAQ. Cold outreach therefore belongs on separate lookalike domains, not subdomains of the brand you protect.
Why does Google Postmaster Tools show no data for my domain?
Your volume is probably below Google’s reporting threshold. At typical cold email pacing of 20 to 30 sends per day per mailbox, the daily sample reaching personal Gmail accounts is often too small to display, and that is normal rather than an error. Watch bounce codes and your reply-rate baseline as the early warning instead. A cold email automation tool that manages sending infrastructure watches these signals continuously across every connected account.
Is Sender Score accurate for Gmail or Outlook placement?
Treat it as directional, not authoritative. Sender Score is Validity’s 0 to 100 rating of your sending IP, built from complaint, trap, and volume data on a rolling 30-day average, per Validity. Gmail and Microsoft score your mail with their own first-party systems, not Validity’s number. A falling score is a smoke alarm; the fire is confirmed in Postmaster Tools and SNDS.
Check reputation weekly, or let the checking run itself
To check email domain reputation properly: verify every sending domain in Google Postmaster Tools on day one, read spam rate, compliance status, and authentication weekly, add SNDS if you control your IPs, and cross-check with a Sender Score lookup and a seed test when the picture is ambiguous. Keep the spam rate under the 0.1 percent target from Google’s sender guidelines, and when a reading dips, run the triage order from blacklist scan down to re-warm rather than guessing at copy changes.
The weekly discipline is the part busy teams drop, and it is the part that decides whether the other work matters. GTM Bud runs that layer for you: campaigns send on managed infrastructure with warmup, conservative pacing, and continuous deliverability monitoring, for a flat monthly rate per connected sending account, backed by the same guarantee our agency carries, 1.5 percent positive replies on email or a full refund. Start with the cold email automation tool, or hand off the entire motion as done-for-you outbound and let the dashboards be someone else’s Monday checklist.