Real-time email delivery metrics across major providers
Last updated: Jul 31, 2026 9:05 AM PDT

Current ESP Status
Provider P95 Latency (s) Retry Rate Trend Status Details
Apple iCloud 3.59 0.0% Degraded View Details
Comcast / Xfinity 1.40 1.0% Healthy View Details
GMX / WEB.de 1.94 0.0% Healthy View Details
Google Mail 0.77 0.3% Healthy View Details
Microsoft 365 1.53 0.3% Healthy View Details
Outlook / Hotmail 1.55 0.0% Healthy View Details
Spectrum / Charter 1.47 0.8% Healthy View Details
Yahoo / AOL 1.46 0.0% Healthy View Details

Details for Apple iCloud

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P95 Latency (24 hours)
Delivery Issues (24 hours)
Retry and Bounce Rates
Top Delivery Failure Reasons (24 hours)
Reason Distribution
Temporary resource unavailable
59.0%
Apple CS01 policy rejection
32.6%
Mailbox over quota
4.9%
Apple HM08 policy rejection
1.6%
Unknown
1.4%
Invalid address (user doesn't exist)
0.4%
Network error (timeout/refused/reset)
0.2%

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?

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