Outage in Anthropic
Degraded performance for multiple models
Resolved MinorIncident Report
Summary AI Generated
On August 18, 2026, Anthropic experienced elevated errors and degraded performance across multiple Claude models—including Mythos 5, Fable 5, Opus 5, Sonnet 5, and Haiku 4.5—affecting both api.anthropic.com and claude.ai for approximately 2.7 hours. The incident narrowed in scope to primarily Claude Opus 5, with impact confirmed between 16:11 and 18:23 UTC. A fix was implemented and the issue was fully resolved by 19:01 UTC.
We are investigating reports of degraded performance affecting multiple models. We will provide an update as soon as possible.
Trusted by 1,000+ teams
The Status Page Aggregator with Early Outage Detection
Stop finding out about outages from your users. Monitor 6,320+ cloud services and get alerted the second something breaks.
Latest Updates ( sorted recent to last )
RESOLVED
3 days ago - at 08/18/2026 07:01PM
The issue affecting Claude Opus 5 has been resolved. Impact occurred from 16:11 to 18:23 UTC.
MONITORING
3 days ago - at 08/18/2026 06:26PM
A fix has been implemented and we are monitoring the results.
INVESTIGATING
3 days ago - at 08/18/2026 05:12PM
We are investigating elevated errors on requests to Claude Opus 5. We will provide an update as soon as possible.
INVESTIGATING
3 days ago - at 08/18/2026 04:20PM
We are investigating elevated errors on requests to Claude Mythos 5, Claude Fable 5, Claude Opus 5, Claude Sonnet 5, Claude Haiku 4.5, and other Claude models. We will provide an update as soon as possible.
INVESTIGATING
3 days ago - at 08/18/2026 04:20PM
We are investigating reports of degraded performance affecting multiple models. We will provide an update as soon as possible.
Latest Anthropic outages
Elevated errors on requests to multiple models - about 19 hours ago
Elevated errors on Google connectors - about 20 hours ago
Service disruption on Claude services - 5 days ago
The Status Page Aggregator with Early Outage Detection
With IsDown, you can monitor all your critical services' official status pages from one centralized dashboard and receive instant alerts the moment an outage is detected. Say goodbye to constantly checking multiple sites for updates and stay ahead of outages with IsDown.
Start free trialNo credit card required · Cancel anytime · 6320 services available
Integrations with
