Outage in Claude

Degraded performance for multiple models

Resolved Minor

August 18, 2026 - Started 1 day ago - Lasted about 3 hours
Official incident page

Incident Report

Summary AI Generated

Claude experienced degraded performance across multiple models — including Claude Opus 5, Sonnet 5, Haiku 4.5, and others — affecting both the API and claude.ai for approximately 2.7 hours on August 18, 2026 (16:11–18:23 UTC). Users encountered elevated errors, infinite loading, repeated failed attempts, and "server busy" messages that rendered the service effectively unusable. A fix was implemented and the incident 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.

Components affected

Claude api.anthropic.com Claude claude.ai

Latest Updates ( sorted recent to last )

RESOLVED 1 day 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 1 day ago - at 08/18/2026 06:26PM

A fix has been implemented and we are monitoring the results.

INVESTIGATING 1 day 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 1 day 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 1 day 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 Claude outages

Degraded performance for Claude Opus 5 and Claude Haiku 4.5 - about 19 hours ago

Degraded performance for Claude Opus 5, Claude Sonnet 5 - 3 days ago

Service disruption on Claude services - 3 days ago

Elevated errors for Claude Mythos 5, Claude Fable 5, and Claude Sonnet 5 - 7 days ago

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