# Anthropic Claude Sonnet 4 — deprecation status

> Yes — Claude Sonnet 4 is retired. Anthropic deprecated it on April 14, 2026 and shut it down on June 15, 2026; API requests to it now fail. The recommended replacement is Claude Sonnet 4.6.

The workhorse of the Claude 4 generation, and for a year the default in Claude Code. Retired June 15, 2026 in the same announcement as Opus 4.

## Facts

| Field | Value |
| --- | --- |
| Provider | Anthropic |
| Model id | `claude-sonnet-4-20250514` |
| Status | Retired |
| Aliases | `claude-sonnet-4-0` |
| Released | May 14, 2025 |
| Deprecated | April 14, 2026 |
| Shutdown | June 15, 2026 (45 days ago) |
| Last verified | July 30, 2026 |

## Replacement

- **Claude Sonnet 4.6** (`claude-sonnet-4-6`) · recommended — https://modeldeprecations.dev/anthropic/claude-sonnet-4-6
  - Sonnet 4.6 keeps the same pricing and raises the context window to 1M tokens. Its adaptive thinking replaces the explicit thinking budget Sonnet 4 used, so any code setting thinking.budget_tokens needs review.
  - Parameters it accepts: https://modelparams.dev/models/anthropic/claude-sonnet-4-6

```diff
- "model": "claude-sonnet-4-20250514"
+ "model": "claude-sonnet-4-6"
```

## FAQ

### When did Anthropic Claude Sonnet 4 shut down?

Anthropic Claude Sonnet 4 shut down on June 15, 2026. API requests to it fail from that date onward.

### What replaces Anthropic Claude Sonnet 4?

Anthropic recommends Claude Sonnet 4.6 (`claude-sonnet-4-6`) as the replacement for Anthropic Claude Sonnet 4. Sonnet 4.6 keeps the same pricing and raises the context window to 1M tokens. Its adaptive thinking replaces the explicit thinking budget Sonnet 4 used, so any code setting thinking.budget_tokens needs review.

### Is Anthropic Claude Sonnet 4 still available?

No. Anthropic Claude Sonnet 4 is retired and no longer served — it was shut down on June 15, 2026. Calls to it return an error.

### How do I migrate from Anthropic Claude Sonnet 4 to claude-sonnet-4-6?

Swap the model id in your API call: replace "claude-sonnet-4-20250514" with "claude-sonnet-4-6". Sonnet 4.6 keeps the same pricing and raises the context window to 1M tokens. Its adaptive thinking replaces the explicit thinking budget Sonnet 4 used, so any code setting thinking.budget_tokens needs review.

### Does this apply to claude-sonnet-4-0 too?

Yes. Anthropic Claude Sonnet 4 is also published as `claude-sonnet-4-0`; that id shares the same lifecycle dates as `claude-sonnet-4-20250514`.

## Sources

- [Anthropic model deprecations](https://platform.claude.com/docs/en/about-claude/model-deprecations) — accessed 2026-07-30

---

Canonical page: https://modeldeprecations.dev/anthropic/claude-sonnet-4-20250514
JSON: https://modeldeprecations.dev/api/v1/models/anthropic/claude-sonnet-4-20250514.json