Every domain that sends email has a reputation score. It isn't displayed anywhere publicly — inbox providers like Gmail and Outlook maintain it internally — but it determines whether your emails land in the inbox, promotions tab, or spam folder.
Understanding how this score works is the difference between a 2% reply rate and an 8% reply rate on identical copy.
How inbox providers calculate reputation
Reputation is a composite signal. No provider publishes their exact formula, but from years of data and Google's own Postmaster Tools documentation, we know the main factors:
Positive signals (raise your score)
- Emails being opened
- Replies being sent back
- Emails moved from spam or promotions to the inbox
- Emails marked as important or starred
- Consistent send volume over time
Negative signals (lower your score)
- Emails marked as spam
- Emails deleted without being opened
- High bounce rate (sending to invalid addresses)
- Sudden volume spikes
- Authentication failures (missing SPF/DKIM/DMARC)
What the Inboxrise score means
Inboxrise aggregates warmup engagement data into a 0–100 score that updates daily. Here's how to interpret it:
How long does it take to build reputation?
For a brand new domain with proper authentication (SPF/DKIM/DMARC), running consistent warmup:
- Day 7: Score typically 20–35. Early signals established.
- Day 14: Score typically 45–60. Safe for very low-volume campaigns.
- Day 21: Score typically 65–75. Most domains are ready to send campaigns.
- Day 30: Score typically 75–90. Full reputation, sustainable for 50+ emails/day.
Why reputation decays
Reputation isn't permanent. If you stop sending (even for two weeks), your score begins to decay — inbox providers treat inactive senders as lower-quality. This is why we recommend keeping warmup running permanently at a low volume, even when you're not running active campaigns.
A score drop of 10–15 points after a two-week pause is normal. Restart warmup and it will recover within a week.
How to monitor your reputation
Three tools worth using alongside Inboxrise:
- Google Postmaster Tools (postmaster.google.com) — the gold standard for Gmail reputation monitoring. Register your domain and you'll get a domain reputation dashboard directly from Google.
- Microsoft SNDS — Microsoft's equivalent for Outlook/Hotmail deliverability data.
- MXToolbox — check if your domain or IP is on any major blacklists.
Bottom line: Reputation is the invisible infrastructure of cold email. You can't see it in your sent folder, but every inbox provider sees it the moment your email arrives. Build it carefully, protect it actively, and it will compound over time into consistently high inbox placement.