How to Check Your Email Domain Reputation
Learn how to check your domain's email reputation using free tools, understand reputation scores, and improve your domain's standing with email providers.
Your domain reputation determines whether your emails reach the inbox or land in spam. Email providers maintain reputation scores for every sending domain, and those scores directly impact deliverability. Here's how to check and improve yours.
What Is Domain Reputation?
Domain reputation is a score that email providers assign to your domain based on:
- Sending history — Volume, consistency, patterns
- Spam complaints — Percentage of recipients marking mail as spam
- Bounce rates — How many emails fail to deliver
- Engagement — Opens, clicks, replies
- Authentication — SPF, DKIM, DMARC status
- Spam trap hits — Sending to known trap addresses
Each email provider maintains their own reputation score for your domain. Your reputation at Gmail may differ from Outlook.
Tools to Check Domain Reputation
Google Postmaster Tools
Best for: Gmail reputation specifically
How to access:
- Go to postmaster.google.com
- Add and verify your domain
- View domain reputation dashboard
Reputation levels:
- High — Best possible delivery
- Medium — Generally good
- Low — Increased spam filtering
- Bad — Severe delivery problems
Microsoft SNDS
Best for: Outlook.com, Hotmail reputation
How to access:
- Go to sendersupport.olc.protection.outlook.com
- Register and verify your IPs
- View data on your IP reputation
Provides:
- IP reputation status
- Spam trap hits
- Complaint rates
Sender Score by Validity
Best for: Overall sending reputation
How to access:
- Go to senderscore.org
- Enter your sending IP address
- View your score (0-100)
Score interpretation:
- 80-100: Excellent
- 70-79: Good
- 60-69: Fair
- Below 60: Poor
Talos Intelligence (Cisco)
Best for: IP and domain reputation lookup
How to access:
- Go to talosintelligence.com
- Enter your domain or IP
- View reputation rating
Ratings:
- Good
- Neutral
- Poor
Barracuda Central
Best for: Checking Barracuda reputation
How to access:
- Go to barracudacentral.org
- Enter your IP address
- Check if listed and reputation status
What Affects Domain Reputation
| Factor | Impact | How to Monitor |
|---|---|---|
| Spam complaints | Very High | Postmaster tools, feedback loops |
| Bounce rates | High | Email service reports |
| Spam trap hits | High | SNDS, list hygiene |
| Engagement rates | Medium | Email analytics |
| Authentication | Medium | DMARC reports |
| Sending patterns | Medium | Volume consistency |
Spam Complaints
Target: Below 0.1% Critical threshold: Above 0.3%
Even a small percentage of complaints significantly impacts reputation.
Bounce Rates
Soft bounces: Temporary issues (mailbox full) Hard bounces: Permanent failures (address doesn't exist)
Target: Hard bounces below 2%
Spam Trap Hits
Spam traps are email addresses used to catch spammers:
- Pristine traps: Never belonged to real users
- Recycled traps: Abandoned addresses repurposed as traps
Hitting spam traps severely damages reputation.
Checking Reputation Step by Step
Check Google Postmaster Tools
Set up and monitor your Gmail-specific reputation.
Check Sender Score
Get your overall reputation score for your sending IP.
Check blacklists
Verify you're not on any email blacklists.
Review authentication
Ensure SPF, DKIM, and DMARC are properly configured.
Monitor engagement
Track open rates, click rates, and complaint rates.
Improving Domain Reputation
Quick Wins
- Fix authentication — Ensure SPF, DKIM, DMARC all pass
- Remove bad addresses — Clean bounced emails from lists
- Honor unsubscribes — Process immediately
- Reduce complaints — Make unsubscribe easy and visible
Long-term Improvements
- List hygiene — Regular cleaning of inactive subscribers
- Engagement-based sending — Send more to engaged users
- Consistent volume — Avoid sudden spikes
- Warm up gradually — Increase volume slowly
If Reputation Is Bad
Stop problematic sending
Pause campaigns until you identify the issue.
Identify the cause
Review complaints, bounces, and sending practices.
Fix the root problem
Address list quality, content, or technical issues.
Reduce volume dramatically
Send only to your most engaged subscribers.
Rebuild gradually
Slowly increase volume while monitoring metrics.
Domain vs IP Reputation
Both matter, but they're different:
| Aspect | Domain Reputation | IP Reputation |
|---|---|---|
| Tied to | Your domain name | Sending server IP |
| Affected by | All email from domain | Email from that IP |
| Shared vs dedicated | Always yours | May be shared |
| Portability | Moves with you | Stays with IP |
When You Use Shared IPs
If using an ESP's shared IP addresses:
- Domain reputation matters more
- You inherit some IP reputation from others
- Focus on what you control (domain)
When You Use Dedicated IPs
With dedicated IPs:
- You control both reputations
- IP must be warmed up from scratch
- Both domain and IP reputation matter equally
Interpreting Reputation Data
What "Good" Looks Like
- Gmail Postmaster: High reputation
- Sender Score: 80+
- Spam complaints: < 0.1%
- Bounce rates: < 2%
- No blacklist listings
Warning Signs
- Reputation dropping over time
- Spike in complaints after campaigns
- Increasing bounce rates
- Blacklist appearances
Red Flags
- Gmail Postmaster: Bad reputation
- Sender Score: Below 60
- Spam complaints: > 0.3%
- Multiple blacklist listings
Reputation takes time to build but can be damaged quickly. One bad campaign can undo months of good behavior.
Monitoring Schedule
| Frequency | Check |
|---|---|
| Daily (during campaigns) | Complaint rates, bounces |
| Weekly | Postmaster Tools, engagement metrics |
| Monthly | Sender Score, blacklists, full audit |
| Quarterly | Strategy review, list cleaning |
Free Tools Summary
| Tool | What It Checks | URL |
|---|---|---|
| Google Postmaster | Gmail reputation | postmaster.google.com |
| Microsoft SNDS | Outlook reputation | sendersupport.olc.protection.outlook.com |
| Sender Score | Overall IP reputation | senderscore.org |
| Talos Intelligence | Domain/IP reputation | talosintelligence.com |
| MXToolbox | Blacklists | mxtoolbox.com/blacklists.aspx |
Check Your Email Authentication
Proper authentication is the foundation of good domain reputation. Verify your SPF, DKIM, and DMARC.
Domain reputation isn't a single score—it's an ongoing assessment by every email provider you send to. Regular monitoring, good sending practices, and proper authentication build the reputation that keeps your emails in the inbox.