Why Claude AI Is Not Working: Causes and Fixes

If Claude AI won't load, keeps spinning, throws an error, or stops mid-response, the cause is almost always one of five things: an ongoing outage, a browser/cache problem, hitting your plan's usage limit, a login/session issue, or a network restriction (VPN, firewall, ad blocker). None of these mean your account is broken — they just need different fixes.

Start by ruling out the simplest explanation: Claude itself might be down or degraded. Check Anthropic's status page before touching any settings, since no amount of clearing cache will fix a server-side outage. If the status page shows all green, work through the checklist below in order — it covers roughly 90% of "Claude AI is not working" reports.

1. Confirm it's not an outage

Anthropic publishes real-time incident updates. Before debugging locally:

• Check the official Claude status page for active incidents
• Search "Claude down" on X/Twitter — outages usually get reported within minutes
• Try a different network (mobile data instead of Wi-Fi) to rule out local issues

If there's a confirmed outage, waiting is the only fix. This is also the most common reason Claude works fine one hour and fails the next with no changes on your end.

2. Clear browser state

Web app issues (blank screen, chat not sending, stuck "thinking" indicator) are frequently caused by stale cached assets or a conflicting browser extension.

• Hard refresh: Ctrl+Shift+R (Windows/Linux) or Cmd+Shift+R (Mac)
• Clear cookies and cached files specifically for claude.ai
• Disable ad blockers, privacy extensions, and script blockers one at a time — these frequently break streaming responses by killing long-lived connections
• Try an incognito/private window to isolate extension conflicts
• Try a different browser entirely (Chrome vs. Firefox vs. Safari) to confirm it's not browser-specific

If Claude works fine in incognito mode but not in your normal window, an extension is the culprit.

3. Check your usage limits

Claude AI's free and Pro tiers have message caps that reset on a rolling window. If you suddenly can't send a message, or get a "you've reached your limit" notice, this is expected behavior, not a bug.

• Free tier: limited messages per rolling period, shared across the account
• Pro: significantly higher limits, but still capped, especially during high-demand periods
• Limits reset on a timer shown in the app — check the message composer for the countdown

This is also the most common cause of Claude AI "not working" during business hours in high-traffic time zones, when demand spikes push more users against shared capacity.

4. Log out and back in

Session tokens occasionally go stale, especially after a password change, a long period of inactivity, or a browser update. Logging out, clearing cookies for the domain, and logging back in resolves a surprising number of "stuck loading" and "can't send message" reports.

If you use SSO (Google login) and it's failing, check whether your organization's Google Workspace settings changed recently — this can silently break third-party app access.

5. Rule out network restrictions

Corporate networks, school networks, and some VPNs block or throttle streaming connections, which is how Claude delivers responses token-by-token. Symptoms include: the chat sends but no response ever appears, or responses cut off after a few words.

• Try Claude on a personal network or mobile hotspot
• If it works there, the issue is a firewall or proxy blocking WebSocket/streaming traffic
• Ask your network admin to allowlist claude.ai if this is a recurring work-network issue

6. Mobile app specific issues

The iOS and Android apps have their own failure modes separate from the web app:

• Force-close and reopen the app (don't just background it)
• Check for a pending app update in the App Store / Play Store
• Reinstall if the app crashes on launch — this clears corrupted local storage
• Confirm notification/background permissions aren't blocking network calls

7. Check what you're actually asking Claude to do

Sometimes "not working" means Claude is responding, just not the way you expect:

• Extremely long conversations can hit context limits, causing Claude to lose earlier details or truncate
• Certain requests (real-time data, browsing live URLs Claude can't access) will produce a response, just not a useful one
• Uploaded files that are too large or in unsupported formats fail silently in some flows

This isn't a bug — it's a limitation worth knowing before assuming something's broken.

When you need Claude in a product, not a chat window

If you're troubleshooting Claude AI because you're trying to build something on top of it — a support bot, an internal tool, a feature in your app — the browser chat interface was never designed for that. It has no API keys, no usage metadata, no team management, and its rate limits are tuned for human conversation, not application traffic.

SubToAPI turns your existing Claude access into a proper HTTPS API: application keys (sub_live_...), streaming, tool use, and usage tracking in one dashboard, so your app talks to a stable endpoint instead of a browser session that can log out or hit consumer limits.

curl https://api.subtoapi.app/v1/messages \
  -H "Authorization: Bearer $SUBTOAPI_KEY" \
  -H "content-type: application/json" \
  -d '{
    "model": "claude-sonnet-4",
    "max_tokens": 1024,
    "messages": [{"role": "user", "content": "Hello"}]
  }'

Setup takes a few minutes via the quickstart guide, and there's a free trial at signup if you want to try it before committing to a plan.

questions

Is Claude AI down right now? Check Anthropic's official status page first — it's updated in real time and will confirm whether an outage is affecting all users or just you.

Why does Claude AI say I've reached my limit? Free and Pro plans have rolling message caps. The limit resets on a countdown shown in the message box; upgrading or waiting it out are the only fixes.

Why does Claude AI keep loading forever? Usually a stale browser cache, a conflicting extension, or a network blocking streaming connections. Try incognito mode and a different network to isolate the cause.