Anthropic experienced a minor incident on August 18, 2026 affecting claude.ai and Claude API (api.anthropic.com) and 1 more component, lasting 2h 41m. The incident has been resolved; the full update timeline is below.
Affected components
Update timeline
- investigating Aug 18, 2026, 04:20 PM UTC
We are investigating reports of degraded performance affecting multiple models. We will provide an update as soon as possible.
- investigating Aug 18, 2026, 04:20 PM UTC
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 Aug 18, 2026, 05:12 PM UTC
We are investigating elevated errors on requests to Claude Opus 5. We will provide an update as soon as possible.
- monitoring Aug 18, 2026, 06:26 PM UTC
A fix has been implemented and we are monitoring the results.
- resolved Aug 18, 2026, 07:01 PM UTC
The issue affecting Claude Opus 5 has been resolved. Impact occurred from 16:11 to 18:23 UTC.