Claude 4 Shutdown FAQ: 25 Questions Every Developer Is Asking

2. Is Claude 4 completely gone?

Yes. Claude 4 Opus and Claude Sonnet 4 are fully retired. The model IDs claude-4-opus and claude-4-sonnet no longer work. There is no way to access them.

3. When exactly did Claude 4 shut down?

June 15, 2026. API calls to the deprecated model IDs started returning 410 errors immediately. There was no advance warning in the API response — your code just started failing.

4. What does the 410 error actually mean?

HTTP 410 Gone means "the resource has been permanently removed." It's different from 404 (not found) — Anthropic is explicitly telling you the model existed but is gone forever. This signals you should update your code, not retry.

5. Will Claude 4 ever come back?

No. Anthropic has confirmed the retirement is permanent. Claude 4 Opus and Sonnet 4 are not coming back. The successor models (Claude Opus 4.8, Claude Sonnet 4.6) are the supported replacements.

6. What replaced Claude 4?

Anthropic's official successors:

• Claude Opus 4.8 — $5/$25 per 1M tokens (67% cheaper than Claude 4 Opus)
• Claude Sonnet 4.6 — $3/$15 per 1M tokens (same price as Sonnet 4, 5x context window)

Same API format, same API key, same SDK. Just change the model name string. See our complete replacement guide.

7. What's the cheapest alternative to Claude 4?

If you want to save the most money:

Use our free cost calculator to estimate your exact savings based on your usage.

8. Should I stay with Anthropic or switch providers?

Stay with Anthropic if: You want the easiest migration (same API key, same SDK, just change model name). Claude Opus 4.8 is still excellent and 67% cheaper.

Switch providers if: You want maximum savings. DeepSeek V4 Pro is 97% cheaper with comparable quality. But you'll need a new API key and may need to adjust your code slightly.

See our side-by-side comparison for the full breakdown.

9. Is Claude Opus 4.8 as good as Claude 4 Opus?

Claude Opus 4.8 is the successor model. It has improved reasoning, better coding ability, and a larger context window (200K vs 200K). In benchmarks, it outperforms Claude 4 Opus on most tasks. It's a strict upgrade.

10. Is Claude Sonnet 4.6 worth the upgrade?

Yes. Same price as Claude Sonnet 4 ($3/$15) but with 5x the context window (1M tokens vs 200K) and improved reasoning. It's a free upgrade — no additional cost.

11. How do I fix Claude 4 API errors?

Two steps:

1. Search your code for claude-4-opus and claude-4-sonnet
2. Replace with claude-opus-4-8 or claude-sonnet-4-6

That's it. No other changes needed. Same API key, same SDK, same request format. See the complete fix guide.

12. Do I need a new API key?

If staying with Anthropic: No. Your existing API key works with Claude Opus 4.8 and Sonnet 4.6. Only the model name changes.

If switching providers: Yes. You'll need a new API key from DeepSeek, OpenAI, Google, or another provider.

13. What if I'm using LangChain, LlamaIndex, or another framework?

Most frameworks use the same model name parameter. Update the model name in your configuration:

# LangChain
ChatAnthropic(model="claude-opus-4-8")

# LlamaIndex
ChatBedrock(model="claude-opus-4-8")

# OpenAI SDK (compatible)
client.chat.completions.create(model="claude-opus-4-8")

14. How long does migration take?

Most developers complete migration in 5-15 minutes. The change is typically 1-2 lines of code (the model name string). The hardest part is finding all the places where the model name appears in your codebase.

15. What if I have Claude 4 hardcoded in multiple places?

Use your IDE's find-and-replace across all files:

# VS Code: Cmd+Shift+H
Find: claude-4-opus
Replace: claude-opus-4-8

# Or use grep to find all instances:
grep -r "claude-4-opus" ./src

16. DeepSeek vs Claude Opus 4.8 — which should I choose?

DeepSeek V4 Pro ($0.435/$0.87): 97% cheaper, excellent for most tasks, slightly lower quality on complex reasoning.

Claude Opus 4.8 ($5/$25): 67% cheaper, identical API, best quality for complex tasks.

If cost is your priority, DeepSeek. If quality and simplicity are your priority, stay with Anthropic.

17. Is GPT-5 a good Claude 4 replacement?

GPT-5 at $1.25/$10 per 1M tokens is 87% cheaper than Claude 4 Opus. It's a strong alternative for general tasks, but the API format is different (OpenAI vs Anthropic). You'll need to adjust your code.

18. What about Gemini 2.5 Pro?

Gemini 2.5 Pro at $1.25/$10 is also 87% cheaper. Google's API is OpenAI-compatible, so migration is straightforward if you're using a standard client library.

19. Which alternative has the best code quality?

For code generation specifically:

1. Claude Opus 4.8 — best overall code quality
2. Claude Sonnet 4.6 — excellent code, 80% cheaper
3. DeepSeek V4 Pro — very good code, 97% cheaper
4. GPT-5 — strong code, 87% cheaper

Use our Code Quality Comparison Tool to test with your specific prompts.

20. What's the best drop-in replacement (no code changes)?

Claude Opus 4.8 or Claude Sonnet 4.6. Same provider, same API key, same SDK, same request format. Change one string in your code and you're done.

21. Will my Anthropic bill change?

It depends on which model you migrate to:

• Claude Opus 4.8: 67% cheaper than Claude 4 Opus ($5/$25 vs $15/$75)
• Claude Sonnet 4.6: Same price as Claude Sonnet 4 ($3/$15) but 5x context

Use our cost calculator to estimate your new bill.

22. How much can I save by switching to DeepSeek?

At typical usage (1M input tokens, 500K output tokens/month):

23. Is there a free tier for any Claude 4 alternatives?

Most providers offer free tiers or trial credits:

• Anthropic: No free tier for Opus 4.8, but Sonnet 4.6 has limited free usage
• DeepSeek: Free tier available with rate limits
• Google: Free tier for Gemini models with usage caps
• OpenAI: Trial credits for new accounts

24. Should I migrate to multiple providers for redundancy?

Yes, this is smart. After experiencing the Claude 4 shutdown, many developers are implementing multi-provider strategies:

1. Primary: Claude Opus 4.8 (best quality)
2. Fallback: DeepSeek V4 Pro (cheapest)
3. Emergency: Gemini 2.5 Pro (different provider)

Use our Developer Toolkit for multi-provider code patterns.

25. What's the fastest way to get back online?

Right now, do this:

1. Open your codebase
2. Find claude-4-opus → replace with claude-opus-4-8
3. Find claude-4-sonnet → replace with claude-sonnet-4-6
4. Deploy

Total time: 2-5 minutes. Your API calls will work immediately.