Real-time email delivery metrics across major providers
Last updated: Dec 27, 2025 9:50 PM PST
Current ESP Status
| Provider | P95 Latency (s) | Retry Rate | Trend | Status | Details |
|---|---|---|---|---|---|
| Apple iCloud | 2.46 | 13.3% | ▬ | Issues | View Details |
| Comcast / Xfinity | 1.33 | 36.0% | ▬ | Issues | View Details |
| GMX / WEB.de | 2.33 | 0.0% | ▲ | Healthy | View Details |
| Google Mail | 0.70 | 3.2% | ▲ | Healthy | View Details |
| Microsoft 365 | 1.70 | 5.1% | ▼ | Degraded | View Details |
| Outlook / Hotmail | 1.96 | 0.0% | ▲ | Healthy | View Details |
| Spectrum / Charter | 0.75 | 0.0% | ▬ | Healthy | View Details |
| Yahoo / AOL | 1.45 | 0.0% | ▲ | Healthy | View Details |
Details for Apple iCloud
← Back to OverviewP95 Latency (24 hours)
Delivery Issues (24 hours)
Retry and Bounce RatesTop Delivery Failure Reasons (24 hours)
| Reason | Distribution |
|---|---|
| Apple CS01 policy rejection |
93.5%
|
| Mailbox over quota |
2.5%
|
| Apple HM08 policy rejection |
1.9%
|
| Temporary resource unavailable |
0.6%
|
| Network error (timeout/refused/reset) |
0.6%
|
| Unknown |
0.5%
|
| Invalid address (user doesn't exist) |
0.5%
|
About this data
- The numbers on this page come from SMTP telemetry that Groups.io collects each day.
- Latency measures the time from the start of the connection until we receive the server's response to the DATA command.
- Metrics are updated every five minutes and down-sampled into 5-minute buckets; raw data older than seven days is automatically purged, and roll-ups are kept for 90 days.
Need deeper, real-time insight?
- Query ANY domain - not just the majors you see above
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