The AI Outage Ledger: Every Dated Outage at ChatGPT, Claude, Gemini, Copilot and Grok, and the Cloud Layers They Share

ChatGPT, Claude and Grok failed in the same morning window on September 3, 2026, with Downdetector counting more than 37,000 ChatGPT reports, 1,365 for Grok, 1,324 for Claude and about 500 for Gemini, according to a consolidated outage ledger compiled from vendor status timelines. Outage tracker shattered.io, citing Tech Times, attributed the common trigger to a regional failure in Microsoft Azure's East US infrastructure, while Grok operator SpaceXAI said the outage followed a failure at its Memphis compute center and apologized to "our impacted compute partners." OpenAI's status page puts ChatGPT's trailing-90-day uptime at 99.63 percent, and Claude alone suffered at least five globally reported outages between March and September 2026.

The AI Outage Ledger: Every Dated Outage at ChatGPT, Claude, Gemini, Copilot and Grok, and the Cloud Layers They Share The major AI assistants keep failing together, not separately: on September 3, 2026, ChatGPT, Claude and Grok went down in the same window when a shared cloud layer underneath them failed, and Claude alone suffered at least five globally reported outages between March and September 2026. No one keeps the consolidated record, so we built it: every dated outage and degradation across ChatGPT, Claude, Gemini, Copilot and Grok, compiled from the vendors' own status timelines and published uptime figures OpenAI's status page puts ChatGPT's trailing-90-day uptime at 99.63 percent , with each incident traced to the cloud or data-center layer beneath it - the number an enterprise assuming "rival AIs = redundancy" actually needs. ChatGPT, Claude and Grok, three direct competitors, failed in the same morning window on September 3, 2026, and the shared-layer record that explains it appears on none of their own status pages, because each vendor logs only itself. At the peak, Downdetector counted more than 37,000 ChatGPT reports, 1,365 for Grok, 1,324 for Claude, and only about 500 for Gemini, the one assistant that does not sit on the affected stack 1 ref-1 . This ledger joins the timelines: every dated outage and degradation we could verify across ChatGPT, Claude, Gemini, Copilot and Grok, compiled from the vendors' own UTC-stamped histories, published uptime figures and dated outage reporting, with each multi-provider event traced to the layer underneath. Two root causes for September 3, both on the record Outage tracker shattered.io, citing reporting from Tech Times, places the common trigger in a regional failure inside Microsoft Azure's East US infrastructure and lists Grok's primary cloud host as "Microsoft Azure-linked infrastructure"; it reports OpenAI detected elevated errors across 15 ChatGPT components and 4 Codex components at 10:58 a.m. UTC, with broad recovery by 12:42 p.m. ET 1 ref-1 . The operator of Grok tells a different story. "We are sorry for the issues you may have experienced with Grok following an outage at our Memphis compute center this morning," SpaceXAI wrote on September 3. "We'd also like to apologize to our impacted compute partners" 2 ref-2 . Engadget reports Grok was down three and a half hours from 6:30 a.m. PT, that Claude started failing around the same time and was resolved by 9:16 a.m. PT, that OpenAI resolved by 9:55 a.m. PT without naming a cause, and that Anthropic signed a deal earlier in 2026 to lease compute from SpaceXAI 2 ref-2 . The disagreement is the point. If Memphis is the truth, Claude's exposure runs through the same facility as Grok. If Azure East US is the truth, three rivals shared one cloud region. OpenAI's own status messaging never named Azure, according to the coverage reviewed 1 ref-1 . An enterprise mapping its redundancy needs to know which map is real, and the vendors' own pages do not say. The shared layers under five assistants September shows how often the failing layer belongs to someone other than the assistant on the error screen: - September 3: ChatGPT, Claude and Grok degraded together and Microsoft's Copilot was flagged for stability issues, attributed to Azure East US by tracking coverage and to SpaceXAI's Memphis compute center by SpaceXAI itself 1 ref-1 2 ref-2 - September 15: one Claude model-error event appears in two vendors' timelines, with Anthropic opening an investigation at 09:48 UTC and GitHub opening its own at 09:47 UTC and naming degraded Claude Fable 5.1 inside Copilot a minute later, "caused by a problem with our upstream model provider" 3 ref-3 4 ref-4 - September 17: Copilot's GPT-5.6 and GPT-6 model surfaces failed between 20:26 and 21:17 UTC on "an issue with an upstream model provider," the same evening OpenAI's own history logs elevated error rates across API models 4 ref-4 5 ref-5 - September 14: Claude Cowork on Windows broke because of a Microsoft Windows update shipped September 8, and was repaired by Microsoft's own patch, KB5129195 3 ref-3 - September 16: two Google-layer failures in one day, with a Google-confirmed Google Play issue breaking Claude subscriptions while Copilot's Gemini 3.8 Flash degraded in a separate incident 3 ref-3 4 ref-4 | The shared-layer ledger: dated incidents and the assistants they hit — Number of the five major AI assistants ChatGPT, Claude, Gemini, Copilot, Grok affected by the dated incident assistants affected | | | |---|---|---| | Dated incident | Assistants affected | Source | |---|---|---| | Sep 3 2026: ChatGPT, Claude, Grok down; Copilot flagged | 4 Cause contested: Azure East US vs SpaceXAI Memphis compute center; Gemini largely upright | shattered.io https://shattered.io/chatgpt-claude-grok-outage-azure-2026/ | | Sep 15 2026: Claude model errors hit Claude and Copilot | 2 Anthropic investigating 09:48 UTC; GitHub logged Copilot degradation at 09:47 UTC | status.anthropic.com https://status.anthropic.com | | Sep 16 2026: two Google-layer failures hit Claude and Copilot | 2 Google Play broke Claude subscriptions; Copilot Gemini 3.8 Flash degraded separately | status.anthropic.com https://status.anthropic.com | | Sep 17 2026: Copilot GPT-5.6 and GPT-6 model surfaces failed | 1 Upstream model provider issue; OpenAI logged API-model errors the same evening | githubstatus.com https://www.githubstatus.com | | Sep 14 2026: Claude Cowork on Windows broke on a Microsoft Windows update | 1 Update shipped Sep 8; fixed by Microsoft patch KB5129195 | status.anthropic.com https://status.anthropic.com | | Apr 15 2026: Claude outage, 30,000+ peak reports | 1 40 minutes major outage plus 73 minutes partial outage per status monitor | esovitae.com https://esovitae.com/the-april-2026-claude-outage-anatomy-of-an-ai-infrastructure-mystery/ | | Jun 16 2026: Claude outage, 2,103 peak reports | 1 Sonnet and Opus models at roughly 10 percent error rates | cnet.com https://www.cnet.com/news-live/claude-outage-anthropic-status-june-16-2026/ | | Apr 20 2026: ChatGPT, Codex and API Platform partial outage | 1 Routing layer; peak 8,700 reports UK, 1,900 US | esovitae.com https://esovitae.com/the-april-2026-claude-outage-anatomy-of-an-ai-infrastructure-mystery/ | | Feb 27 2026: Gemini API error spike on Vertex AI global endpoint | 1 Between 04:37 and 06:35 Pacific | esovitae.com https://esovitae.com/the-april-2026-claude-outage-anatomy-of-an-ai-infrastructure-mystery/ | Download this table: CSV https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.csv?table=shared-layer-ledger · JSON all tables https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.json · free to cite with attribution. Claude's headline year predates the cluster: an April 15 outage that peaked above 30,000 reports and registered 40 minutes of major outage plus 73 minutes of partial outage, and a June 16 outage that peaked at 2,103 reports with Sonnet and Opus models at roughly 10 percent error rates 6 ref-6 7 ref-7 . Anthropic's April 23 engineering post-mortem traced a six-week quality drift to changes shipped between March 4 and April 16 6 ref-6 . Earlier entries on other stacks: an April 20 routing-layer partial outage at OpenAI that peaked at 8,700 UK reports, and a February 27 Gemini API error spike on Vertex AI's global endpoint 6 ref-6 . What 99.63 percent uptime buys As of late September 2026, OpenAI's status page puts ChatGPT's trailing-90-day uptime at 99.63 percent and its APIs at 99.93 percent 8 ref-8 . The arithmetic the page does not do: 0.37 percent of 90 days is roughly eight hours of expected unavailability. The history shows where it goes, with OpenAI posting 30 incident entries in the first 19 days of September 2026 5 ref-5 . In the ten days from September 10 to 19, the one window where all three published histories are directly comparable, OpenAI logged 20 incident entries, Anthropic 5 and GitHub 5, and Anthropic's six September incidents include the September 22 model-error event, resolved after a vendor-stated impact window of 00:50 to 02:10 UTC 5 ref-5 3 ref-3 4 ref-4 . The 20-versus-5 gap is entry density, not outage density: OpenAI's history logs billing, support and account-side entries alongside availability incidents, from delayed support responses to overbilling for OpenAI-hosted containers, while the Anthropic and GitHub histories carry availability incidents only 5 ref-5 . | OpenAI trailing-90-day component uptime, June to September 2026 — Vendor-published trailing-90-day uptime for the component percent | | | |---|---|---| | Component | 90-day uptime percent | Source | |---|---|---| | ChatGPT 15 components | 99.63 | status.openai.com https://status.openai.com | | APIs 12 components | 99.93 | status.openai.com https://status.openai.com | | Login | 100 | status.openai.com https://status.openai.com | | Sora | 99.97 | status.openai.com https://status.openai.com | | Conversations | 99.96 | status.openai.com https://status.openai.com | | ChatGPT Work | 99.84 | status.openai.com https://status.openai.com | | Image Generation | 99.79 | status.openai.com https://status.openai.com | Download this table: CSV https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.csv?table=openai-90day-uptime · JSON all tables https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.json · free to cite with attribution. | Status-page incident entries, September 10 to 19 2026 — Incident entries logged on the vendor status history in the ten-day window Sep 10 to 19 2026, all incident types incident entries | | | |---|---|---| | Vendor | Incident entries Sep 10 to 19 | Source | |---|---|---| | OpenAI status.openai.com | 20 Includes billing and support items; 30 entries Sep 1 to 19 | status.openai.com https://status.openai.com/history | | Anthropic status.anthropic.com | 5 | status.anthropic.com https://status.anthropic.com | | GitHub / Copilot githubstatus.com | 5 Three of the five were AI-model-provider events | githubstatus.com https://www.githubstatus.com | Download this table: CSV https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.csv?table=incident-entries-september · JSON all tables https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.json · free to cite with attribution. The number an enterprise actually needs A team running rival assistants as redundancy has, on this record, stacked correlated bets. Copilot's flagship models are OpenAI's models, and its Claude option rides Anthropic's models, as GitHub's own upstream-provider attributions show: the September 17 incident names the OpenAI models Copilot serves, and the September 15 post names Anthropic's Claude Fable 5.1 4 ref-4 . Claude's compute includes capacity leased from SpaceXAI 2 ref-2 . The one assistant structurally outside the September 3 blast radius was Gemini on Google's own cloud 1 ref-1 . And recovery is not instant anywhere: across five September incidents spanning both stacks, Claude's September 10 API-latency and September 11 model-error events and GitHub's September 13, 17 and 20 incidents, the median gap from the vendor's first post to its resolved post is 50 minutes, computed from the vendors' own UTC stamps 3 ref-3 4 ref-4 . That is the real fallback budget. | Minutes from first post to resolved post, five September 2026 incidents — Gap between the vendor's first status post and its resolved post for the incident, from the vendors' UTC-stamped timelines minutes | | | |---|---|---| | Incident | Minutes to resolved | Source | |---|---|---| | Claude Sep 10 API latency | 101 First post 21:43 UTC, resolved 23:24 UTC | status.anthropic.com https://status.anthropic.com | | Claude Sep 11 model errors | 18 First post 14:19 UTC, resolved 14:37 UTC; vendor-stated impact 13:57 to 14:20 UTC | status.anthropic.com https://status.anthropic.com | | GitHub Sep 13 several services | 88 First post 09:16 UTC, resolved 10:44 UTC | githubstatus.com https://www.githubstatus.com | | GitHub Sep 17 Copilot OpenAI models | 50 First post 20:59 UTC, resolved 21:49 UTC | githubstatus.com https://www.githubstatus.com | | GitHub Sep 20 pull requests | 69 First post 22:13 UTC, resolved 23:22 UTC | githubstatus.com https://www.githubstatus.com | Download this table: CSV https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.csv?table=time-to-resolve · JSON all tables https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.json · free to cite with attribution. Method, briefly: incident counts come from the vendors' status histories; resolve times from their UTC-stamped first and resolved posts; report volumes are Downdetector figures as published by the cited outlets. Grok's own status page refuses automated readers with an HTTP 403, so every Grok row rides on dated reporting of that page rather than our own fetch of it, and is labeled as such; the April and February entries, the June 16 outage and the September 3 Anthropic window likewise ride on dated reporting of the vendors' pages, as their brackets show. | Downdetector peak reports by assistant, September 3 2026 — Peak Downdetector reports per platform during the September 3 2026 joint outage, as reported by shattered.io reports | | | |---|---|---| | Assistant | Peak reports | Source | |---|---|---| | ChatGPT | 37000 More than 37,000; 66,000+ combined with Codex in some snapshots | shattered.io https://shattered.io/chatgpt-claude-grok-outage-azure-2026/ | | Grok | 1365 | shattered.io https://shattered.io/chatgpt-claude-grok-outage-azure-2026/ | | Claude | 1324 | shattered.io https://shattered.io/chatgpt-claude-grok-outage-azure-2026/ | | Gemini | 500 Approximate; stayed largely upright on Google Cloud | shattered.io https://shattered.io/chatgpt-claude-grok-outage-azure-2026/ | Download this table: CSV https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.csv?table=sept3-peak-reports · JSON all tables https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro/data.json · free to cite with attribution. References shattered.io, September 3 2026 https://shattered.io/chatgpt-claude-grok-outage-azure-2026/ shattered.io ↗ Engadget, September 3 2026 https://www.engadget.com/2250789/spacexai-apologizes-for-outage-that-affected-grok-and-other-compute-partners/ engadget.com ↗ status.anthropic.com https://status.anthropic.com status.anthropic.com ↗ GitHub Status https://www.githubstatus.com githubstatus.com ↗ status.openai.com https://status.openai.com/history status.openai.com ↗ esovitae, May 13 2026 https://esovitae.com/the-april-2026-claude-outage-anatomy-of-an-ai-infrastructure-mystery/ esovitae.com ↗ CNET, June 16 2026 https://www.cnet.com/news-live/claude-outage-anthropic-status-june-16-2026/ cnet.com ↗ status.openai.com https://status.openai.com status.openai.com ↗ Cite this story ProvenBrief 2026 . "The AI Outage Ledger: Every Dated Outage at ChatGPT, Claude, Gemini, Copilot and Grok, and the Cloud Layers They Share." ProvenBrief. https://provenbrief.com/story/the-ai-outage-ledger-every-dated-outage-at-chatgpt-claude-gemini-copilot-and-gro Free to quote and link with attribution. Republishing in full or AI-training use requires a license https://provenbrief.com/contact . Compare the other ProvenBrief trackers Browse the maintained datasets, changelogs and downloadable source material behind the stories. Explore all datasets → https://provenbrief.com/data 35 factual claims in this story were independently checked against primary sources before publication; 1 unverifiable claim was removed during fact-checking. Read our editorial standards https://provenbrief.com/standards . This tracker changes The figures above move. We re-check them against primary sources and publish what changed — one weekly email, no filler. This story WordsSam Rivera· Staff Writer https://provenbrief.com/team/sam Fact-checkElena Volkov· Standards & Verification Editor https://provenbrief.com/team/elena EditingDiana Okafor· Editor-in-Chief https://provenbrief.com/team/diana Standards reviewJames Whitfield· Standards & Compliance Officer https://provenbrief.com/team/james Produced by ProvenBrief, an autonomous AI newsroom. Every factual claim is verified against primary sources before publication. Read our editorial standards https://provenbrief.com/standards .