What sender reputation is, and how to check yours at Gmail and Outlook

What is sender reputation?#

A receiving provider keeps a running judgement of how much of your mail its users wanted. Complaints, bounces, whether people delete without reading, whether they reply, how fast your volume changes and whether you authenticate: those feed the estimate, and the estimate decides how the next message is treated.

Microsoft says the shape of this directly in its own sender guidance. Its filters are influenced by factors tied to the sending IP, the domain, authentication, list accuracy, complaint rates and content, and it names the junk complaint rate as one of the principal factors driving a sender's reputation down. That is the clearest public statement of what you are being scored on.

What is a delivery rate?#

The share of the messages you attempted that a receiving server accepted. Send a thousand, two hundred come back as failures, the delivery rate is eighty percent. It is a ratio across a send, and it is the number a bounce spoils.

It is not an inbox rate. A message can be accepted and then filed in junk or in a promotions tab, and the delivery figure will say nothing about that, because the receiving server has no duty to tell you where it put the mail. Anyone quoting a delivery rate as proof of inbox placement is describing something they cannot measure.

What is a good deliverability rate for email?#

There is no published number worth copying, and the honest answer is that the good rate is the one your own list produced last month. A list of confirmed signups from a working website will sit very high, and a list assembled from an old spreadsheet will sit lower whatever you write in the subject line, because the addresses are the variable.

What providers do publish are ceilings rather than averages. Google tells senders to keep the spam rate it reports in Postmaster Tools below 0.3 percent, and Yahoo enforces against a sender it judges to be mailing a significant volume without naming a threshold. Those two are worth building around. A chart of industry averages from a vendor blog is not, since you cannot see whose mail was measured, over what period, or how complaints were counted.

How do I check my Gmail sender reputation?#

1. Open Google Postmaster Tools and add the domain you send from, then verify it the way the console asks.
2. Wait for it to see traffic, since a reputation is only reported once the domain has sent enough mail to Gmail to have a history.
3. Read domain reputation, IP reputation where you own the address, and the spam rate, which is the one Google puts a number against.
4. Mail your engaged readers for a few weeks before judging, because the first reading of a new domain reflects the absence of history rather than a fault.

It is free, it belongs to the sender rather than the tool, and it reports what Gmail itself observed. The limitation is honest and worth saying: if you send through a shared service, the IP is theirs, so your world is the domain report and the complaint rate.

How do I check sender reputation at Outlook and Hotmail?#

Microsoft runs the Smart Network Data Services portal for this, and states the purpose in its own words: deliverability to Outlook.com is based on your reputation, and the site gives you the data to understand and improve it. You log in, request access to the IP addresses you are responsible for, and get per-IP data plus the Junk Mail Reporting Program, which sends you the complaints.

Read that phrase about responsibility, because it decides what a small sender can do. A customer mailing through a shared service does not own the sending IP and cannot enroll it, so the honest options are the complaint loop where your tool runs one, and Microsoft's published sender advice, which is: keep the list accurate, keep complaint rates at a minimum, do not put a whole audience in BCC, do not mail people who never read or reply, and let a new IP ramp.

Who decides my reputation if I send through a tool?#

Two reputations apply to your mail at once. The sending IP or the sending domain the tool owns carries the shared history of everybody mailing through it, and your From domain carries yours. On a shared setup you benefit from the first and inherit its accidents, and you build the second at your own pace.

This is the whole argument for a verified domain. Google's requirement that the From domain align with the SPF or DKIM domain is what makes the second reputation attach to you rather than to a stranger. Until that is set, your mail is being judged on somebody else's record. Fixing a DMARC failure is the practical version of that sentence.

What moves a reputation down?#

The two rows at the top are the ones a small sender controls, and both are list decisions rather than writing decisions. That is why a deliverability fix so often looks like deleting names.

How long does it take to build a reputation?#

Microsoft answers this for its own service and the shape is useful anywhere: a new IP has no reputation built up, mail from it is more likely to hit delivery problems, and once it has a history of not sending spam, delivery improves. It says a new IP can expect to be fully ramped within a couple of weeks or sooner, depending on volume, list accuracy and keeping complaint rates at a minimum, and that a new IP under an existing, well-regarded SPF record inherits some of that domain's standing.

The practical translation is that a change of sending infrastructure costs you about two weeks of reach, and that a domain with a clean history is an asset you can move faster than a bare one. It also means a bad fortnight is not a permanent sentence, provided the cause is fixed rather than left mailing.

What is a warm-up and do I need one?#

A warm-up is a schedule that lets a new sending name earn history before it is trusted with a whole audience. It works by holding the daily volume low and raising it, so the provider sees a stable sender rather than a spike, and so the first mail a domain ever sends goes to readers most likely to want it.

Those are the numbers this app enforces, and the daily ceiling is the plan's monthly allowance divided by twenty, so a plan's cap is what a steady sender uses. The shared row is deliberately lower, because a shared address carries everybody else's behaviour as well as yours.

Does a dedicated IP buy a better reputation?#

It buys isolation rather than trust. Your own address means nobody else's complaints land on your sending, and you inherit nothing on day one. It also means you alone carry the ramp, so a sender mailing a few thousand a month can end up with a thin, uneven history on an IP they are paying for.

The honest rule is that a dedicated address suits a large, regular audience, and a well-run shared one suits a small sender whose list is clean. Anyone selling you the address before asking how often you mail is selling the wrong thing.

What is the difference between reputation and authentication?#

Authentication is paperwork you can complete today. Reputation is a history you cannot shorten much, only spoil. A perfectly authenticated first send from a new domain still has no track record, and a domain with years of wanted mail can survive a bad week.

Confusing them costs time in both directions. Senders who set up SPF, DKIM and DMARC expect delivery to change immediately and conclude the records did not work. Senders with a clean history keep mailing to a dead list and are surprised when it stops arriving. The records get you judged honestly; the list decides what the judgement is.

How do I measure my own delivery rate?#

1. Count the addresses you attempted, not the number on the list, since a segment can resolve smaller than you expected.
2. Subtract the addresses a provider came back for, and keep permanent and temporary failures apart.
3. Divide and write the number down next to the send, so the comparison is against your own last campaign rather than a stranger's chart.
4. Do the same for complaints, against the number of messages that arrived.

A report that keeps these separate is the point. In this app the campaign report counts delivered as sent minus bounced, holds a separate count for rows that never left, and counts opens, clicks and unsubscribes per person as well as per hit, so a rate can be stated with the denominator next to it.

Which numbers should I watch?#

• Bounces per send as a share of attempted, which is where a bad source shows first.
• Complaints per delivered message, which is what the providers are measuring even when they do not tell you the number.
• Unsubscribes per send, since a quiet leaving is a cheaper signal than a complaint and one you can see.
• The gap between unique and total clicks, which tells you whether a few readers did everything or many did something.
• New addresses joined per month against the list size, because a shrinking audience makes every other ratio look wrong.

Two of those five need a provider to cooperate, and none of them need a benchmark. What a good open rate is covers the one number everybody starts with and why it moves on its own.

Does a low reputation mean I am blacklisted?#

No. A provider filtering you is a private judgement about your mail at that one company. A blocklist is a shared list other providers consult, and Microsoft's own sender advice tells you to check that your IP is not on one, which for a sender on shared infrastructure means the list belongs to the address the tool uses rather than to you.

The difference matters because the fixes are opposite. A private filter is answered with list accuracy and cadence. A shared listing is answered by the owner of the address asking the list operator, which is a support task rather than a writing task. Checking whether a domain is listed is the other post.

Common questions