Outage recap · Anthropic

Claude outage — October 21, 2026

On October 21, 2026, Claude had 2 reported incidents on Anthropic's official status page. Below is what was reported — impact, timing, and the AI services the same upstream outage could affect.

Degraded performance for Claude Fable 5

minor
Started
Oct 21, 3:49 PM EDT
Resolved
Oct 21, 4:29 PM EDT
Duration
40 min

Anthropic's updates (2)

  1. investigating · Oct 21, 3:49 PM EDT

    We are investigating elevated errors on requests to Claude Fable 5. We will provide an update as soon as possible.

  2. resolved · Oct 21, 4:29 PM EDT

    The issue affecting other Claude models has been resolved.

What our checks recorded

We checked Claude 8 times from Anthropic's start time to its resolution, once every five minutes. Every one of them reached Claude's site, so this incident did not show up as a failed page load. Our check loads the public site; it cannot see an API error or a broken feature. Median response time was 158 ms, against 202 ms over the 24 hours before. Anthropic posted the incident at Oct 21, 3:49 PM EDT.

Updates are Anthropic's own words from its status page (status: resolved); we never add an inferred cause. The vendor's incident page ↗

Elevated errors affecting Connectors

minor
Started
Oct 21, 11:50 PM EDT
Resolved
Oct 22, 4:07 AM EDT
Duration
4h 17m

Anthropic's updates (3)

  1. investigating · Oct 21, 11:50 PM EDT

    We are investigating elevated errors affecting connectors. We will provide an update as soon as possible.

  2. monitoring · Oct 22, 3:28 AM EDT

    A fix has been deployed for the issue affecting claude.ai and Claude Cowork and we are monitoring for recovery.

  3. resolved · Oct 22, 4:07 AM EDT

    The issue affecting claude.ai and Claude Cowork has been resolved.

What our checks recorded

We checked Claude 52 times from Anthropic's start time to its resolution, once every five minutes. Every one of them reached Claude's site, so this incident did not show up as a failed page load. Our check loads the public site; it cannot see an API error or a broken feature. Median response time was 237 ms, against 204 ms over the 24 hours before. Anthropic posted the incident at Oct 21, 11:50 PM EDT.

Updates are Anthropic's own words from its status page (status: resolved); we never add an inferred cause. The vendor's incident page ↗

The AI cascade

Claude depends on Anthropic. When that upstream has an incident, it doesn't hit Claude alone — these AI tools share the dependency and can degrade at the same time:

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Is Claude down right now? →Claude status history →

AIDownCheck is not affiliated with Anthropic. This recap summarizes incidents published on Anthropic's official status page.