The 0.3% ceiling is not a suggestion
Google's bulk sender guidelines have required authentication and a reported spam rate below 0.3% since February 2024. Crossing it moves whole campaigns, not individual messages.
For high-volume senders
At your volume,reputation is the product.
Past a few thousand messages a day, mailbox providers stop judging individual emails and start judging you. The numbers that decide it are published, and most senders never look at them.
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LitInboxes is an email deliverability monitoring platform for businesses and agencies that depend on email for revenue, customer communication, or client results.
The problem
Where it breaks at volume
At small volume these are annoyances. At scale they are revenue.
One bad segment poisons the domain
Reputation attaches to the domain and the IP, not to the campaign. A single aggressive send drags your transactional mail down with it.
Too many surfaces to check by hand
Several sending domains, several IPs behind them, and a blocklist landscape that changes daily. Manual checking stops scaling after about three domains.
Damage is found weeks late
Reputation declines slowly, then delivery falls off a cliff. With no dated history, you cannot tell which change started the slide.
Four sources, four formats, no answer
Your ESP reports delivered, Gmail reports a spam rate, blocklists report listings, DMARC reports report alignment. Nothing reconciles them for you.
The fix
What LitInboxes does about it
Wide coverage, long history, one place where the four sources agree.
- 01
Gmail's numbers, tracked over time
Connect Google Postmaster Tools and the domain reputation and reported spam rate are pulled in and kept, instead of checked by hand when something already feels wrong.
- 02
Twenty-four blocklists, every domain and IP
On Pro the sweep covers 24 lists across each monitored domain and the IPs behind its A and MX records, with the operator's delisting steps when something appears.
- 03
Reputation snapshots per domain and IP
Each sending domain and each IP is scored and stored, so a decline shows up as a trend line rather than a surprise.
- 04
Two years of history
24 months on Pro. When delivery drops you can line the drop up against the record change, the listing, or the send that caused it.
- 05
Verification at list scale
50,000 verification emails a month on Pro, so a large list gets cleaned before the send instead of measured by its bounces.
In the product
The signals, side by side
Authentication, DMARC, deliveries and blocklist state for one domain, each with the trend behind the number rather than today's value alone.
Ready to sendA · 92+3 this week
Provider: Amazon SES|ESP verification: verified|Webhook: active
DNS & authentication
SPF, DKIM, DMARC and MTA-STS, rechecked every 6 hours.
SPF · passDKIM · passDMARC · passMTA-STS · pass
Last checked · 12 min agoMonitor activeIssues: 0
DMARC
99.2%99.2%pass rate, 30 days
912 reports · 48,120 messages
Deliveries
Healthy0.3%bounce rate, 7 days
0.02% complaint rate
Blocklists
Clean0 / 24listed
Spamhaus, Barracuda, SpamCop and 21 more
Recent activity
Infrastructure check completed, no issues12 min ago
DMARC pass rate back above 99%6 hours ago
Delisted from Spamhaus DBL1 day ago
New DKIM selector detected and verified2 days ago
The domain overview, as it looks in the app.
The numbers
The four numbers that decide it
Every one of these is reported by someone else about you. Volume just makes them expensive.
Postmaster spam rate
Gmail's reported spam rate for your domain, day by day, from Postmaster Tools rather than an estimate.
Bad looks likeSustained above 0.3%, where the bulk sender guidelines stop being met.
Domain and IP reputation
Scored snapshots for each sending domain and each IP behind it, kept as a series.
Bad looks likeTwo steps down inside a week, which is a stop-and-look moment.
Blocklist coverage
24 lists on Pro across domains and mail-server IPs, with the return code the operator published.
Bad looks likeSpamhaus ZEN or DBL, which the large providers consult directly.
DMARC pass rate by source
Which of your senders authenticate and align, grouped by source from the aggregate reports.
Bad looks likeAn unaligned source you did not know was sending as you.
The mechanism
Why the published numbers are the only ones that matter at scale
Under a few thousand messages a day, filtering decisions look almost random and a single bad day means nothing. Above it, providers stop evaluating messages and start evaluating you as a sender. Google publishes what it expects from bulk senders, in force since February 2024: authentication with SPF, DKIM and DMARC, a reported spam rate under 0.3%, and one-click unsubscribe in bulk mail. Yahoo's sender requirements say substantially the same thing.
It also publishes your numbers back to you in Postmaster Tools, which makes that the only place Gmail states an opinion about your domain. Everything else available to you is inference. Your ESP's delivered rate cannot see the folder. A seed test samples a handful of mailboxes and tells you about those mailboxes. The four signals that are reported about you, rather than guessed at, are the Postmaster spam rate and reputation, DMARC pass rate grouped by sending source, blocklist state across domains and IPs, and scored reputation snapshots over time.
At scale the work is therefore coverage and history rather than cleverness. Every sending domain, every IP behind its A and MX records, every DKIM selector, checked on a loop, with a long enough trail that a decline can be lined up against the change that caused it. Two years of history is not nostalgia. It is the difference between knowing what happened and arguing about it.
Getting started
Your first thirty minutes
Start with the domains carrying the volume, not the ones that are easy to add.
- 01
Add your sending domains
Highest volume first, then the transactional ones, then anything a third party sends on your behalf.
- 02
Connect Google Postmaster
It is free, and it is the only place Gmail publishes anything about how it sees you.
- 03
Point DMARC reporting here
Aggregate reports name every system sending as you, including the ones nobody authorised.
- 04
Decide what wakes you
Alerts fire on change: listings, record drift, reputation and pass-rate drops. Email on every plan; Slack, Discord and webhooks on Pro.
Pro, $99/mo
See where your volume is costing you.
Honest limits
When LitInboxes is the wrong tool
Three things a high-volume sender might want that LitInboxes does not do.
- You want an IP or mailbox warmup service. Warmup is not part of the product.
- You want per-mailbox seed placement results across providers. LitInboxes is continuous monitoring, not seed testing.
- You want a 100+ blocklist count for the procurement slide. We check 8, or 24 on Pro, and explain why the rest do not move placement.
Questions
Questions from this crowd
What counts as high volume?
Google's bulk sender rules start at 5,000 messages a day to Gmail addresses. Practically, Postmaster data becomes meaningful above a few thousand a day, below which the graphs get gappy.
Do you monitor dedicated IPs?
Yes. Add the sending IP and it is checked against the same blocklists and scored for reputation alongside the domain.
Where does the spam rate come from?
Google Postmaster Tools, which is Gmail's own report about your domain. It is not modelled or inferred.
Can I see which sender broke alignment?
Yes. DMARC aggregate reports are grouped by sending source, so an unaligned system is named rather than implied.
Is 24 blocklists enough at this volume?
Those 24 are the lists mailbox providers actually consult. The long tail rarely changes real placement, and several of those operators charge for removal, which is a business model rather than a signal.
How far back does the history go?
24 months on Pro, 6 months on Growing, 30 days on Starter. Trials keep 30 days.
Pro, $99/mo
See where your volume is costing you.
Other use cases
SaaS and transactional email
A filtered password reset is a churn event that looks like a product bug. Transactional email fails the way infrastructure fails: quietly.
Read the use caseAgencies and consultants
Ten clients, ten DNS zones, no single answer to the Monday morning question: which of these is broken right now?
Read the use case
Related reading
- The Weekly Deliverability Review: What to Check on Every Client DomainFour signals drift without announcing it. Here is what each one means when it moves, the order to triage them in, and where a weekly pass stops being enough.
- Why Is My Email Going to Spam? A Calm DiagnosticSpam placement is almost always an identity or reputation problem, not a wording problem. Work the causes in the order receivers actually weigh them.
See where your volume is costing you.
Run a free health check on one sending domain: authentication, DNS and blocklist state in a single pass.
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