---
title: Claude Haiku 4.5
url: https://platform.claude.com/docs/ja/models/haiku-4-5/overview
description: Claude Haiku 4.5 のリファレンス：ライフサイクルステータス、各プラットフォームでのモデルID、コンテキストウィンドウ、出力制限、料金、移行リソース。Claude Haiku 4.5 はレガシーモデルです。現在の Haiku モデルは Claude Haiku 5.5 です。
---
**Legacy.** Released October 15, 2025.
Although Claude Haiku 4.5 is still available, you should consider migrating to Claude Haiku 5.5. [See Claude Haiku 5.5](https://platform.claude.com/docs/ja/models/haiku-5-5/overview) · [Migrate to Claude Haiku 5.5](https://platform.claude.com/docs/ja/models/haiku-5-5/migration-guide)
Model ID: `claude-haiku-4-5-20251001`
Context window: 200K tokens · Max output: 64K tokens · Input pricing: $1 / MTok · Output pricing: $5 / MTok
[Announcement](https://www.anthropic.com/news/claude-haiku-4-5)
## 現在のラインナップとの比較
| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowledge cutoff |
| :---------------------------------------------------------------------------------- | :------ | :--------- | :----------------- | :------------------- | :------------- | :--------------- |
| [Claude Fable 5.1](https://platform.claude.com/docs/ja/models/fable-5-1/overview) | 1M | 128K | $10 / $50 | Adaptive (always on) | `high` | Jun 2026 |
| [Claude Opus 5.5](https://platform.claude.com/docs/ja/models/opus-5-5/overview) | 1M | 128K | $4 / $20 | Adaptive (always on) | `medium` | Jun 2026 |
| [Claude Sonnet 5.5](https://platform.claude.com/docs/ja/models/sonnet-5-5/overview) | 1M | 128K | $2 / $10 | Adaptive | `high` | Jun 2026 |
| [Claude Haiku 5.5](https://platform.claude.com/docs/ja/models/haiku-5-5/overview) | 1M | 128K | From $0.10 / $0.50 | Adaptive | `medium` | Jun 2026 |
| **Claude Haiku 4.5** (this model) | 200K | 64K | $1 / $5 | Extended | — | Feb 2025 |
* **Context:** 1M tokens is roughly 555k words or 2.5M Unicode characters on the current tokenizer (introduced with Claude Opus 4.7); models before it fit about 750k words in 1M tokens. 200k tokens is roughly 150k words.
* **Max output:** Synchronous Messages API limit. On the Message Batches API, Claude Opus 5.5, Claude Opus 5, Claude Sonnet 5.5, Claude Sonnet 5, Claude Haiku 5.5, Claude Opus 4.8, Claude Opus 4.7, Claude Opus 4.6, and Claude Sonnet 4.6 support up to 300k output tokens with the output-300k-2026-03-24 beta header.
* **Price / MTok:** Input / output, base price per million tokens. Batch API requests are 50% off; prompt caching reads cost 10% of the base input price (2.5% on Claude Fable 5.1 and Claude Mythos 5.1, 5% on Claude Opus 5.5 and Claude Sonnet 5.5). See Pricing for the full list.
* **Thinking:** Adaptive thinking lets the model decide how much to think, steered by effort. Extended thinking is the manual budget\_tokens mode on earlier models.
* **Default effort:** The effort parameter’s default on the Claude API. Models without a value don’t support the parameter.
* **Knowledge cutoff:** Reliable knowledge cutoff: the date through which the model’s knowledge is most extensive and reliable.
## 仕様
### Model IDs
| Platform | Model ID |
| :-------------------------------------------------------------------------------------------------------------------- | :----------------------------------------- |
| Claude API | `claude-haiku-4-5-20251001` |
| Claude API alias | `claude-haiku-4-5` |
| [Amazon Bedrock](https://platform.claude.com/docs/ja/build-with-claude/claude-in-amazon-bedrock) | `anthropic.claude-haiku-4-5` |
| [Amazon Bedrock (InvokeModel)](https://platform.claude.com/docs/ja/build-with-claude/claude-on-amazon-bedrock-legacy) | `anthropic.claude-haiku-4-5-20251001-v1:0` |
| [Google Cloud](https://platform.claude.com/docs/ja/build-with-claude/claude-on-vertex-ai) | `claude-haiku-4-5@20251001` |
| [Microsoft Foundry](https://platform.claude.com/docs/ja/build-with-claude/claude-in-microsoft-foundry) | `claude-haiku-4-5` |
| [Claude Platform on AWS](https://platform.claude.com/docs/ja/build-with-claude/claude-platform-on-aws) | `claude-haiku-4-5` |
### Pricing
| Feature | Value |
| :------------------------------------------------------------------------------------- | :------------------------------- |
| Input | $1 / MTok |
| Output | $5 / MTok |
| [5m cache write](https://platform.claude.com/docs/ja/build-with-claude/prompt-caching) | $1.25 / MTok |
| [1h cache write](https://platform.claude.com/docs/ja/build-with-claude/prompt-caching) | $2 / MTok |
| [Cache read](https://platform.claude.com/docs/ja/build-with-claude/prompt-caching) | $0.10 / MTok |
| [Batch API](https://platform.claude.com/docs/ja/build-with-claude/batch-processing) | 50% discount on input and output |
[Full price list](https://platform.claude.com/docs/ja/about-claude/pricing)
### Capabilities
| Feature | Value |
| :-------------------------------------------------------------------------------------- | :--------------------- |
| [Context window](https://platform.claude.com/docs/ja/build-with-claude/context-windows) | 200K tokens |
| Max output | 64K tokens |
| [Thinking](https://platform.claude.com/docs/ja/build-with-claude/thinking) | Extended |
| [Default effort](https://platform.claude.com/docs/ja/build-with-claude/effort) | Not supported |
| Input → output | Text and images → text |
| Reliable knowledge cutoff | Feb 2025 |
| Training data cutoff | Jul 2025 |
### Availability
| Feature | Value |
| :---------------------------------------------------------------------------- | :--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [Status](https://platform.claude.com/docs/ja/about-claude/model-deprecations) | Active (legacy) |
| Released | October 15, 2025 |
| Retirement | Not sooner than October 15, 2026 |
| Platforms | Claude API, [Amazon Bedrock](https://platform.claude.com/docs/ja/build-with-claude/claude-in-amazon-bedrock), [Amazon Bedrock (InvokeModel)](https://platform.claude.com/docs/ja/build-with-claude/claude-on-amazon-bedrock-legacy), [Google Cloud](https://platform.claude.com/docs/ja/build-with-claude/claude-on-vertex-ai), [Microsoft Foundry](https://platform.claude.com/docs/ja/build-with-claude/claude-in-microsoft-foundry), [Claude Platform on AWS](https://platform.claude.com/docs/ja/build-with-claude/claude-platform-on-aws) |
## 知っておくとよいこと
* `claude-haiku-4-5` は、固定スナップショット `claude-haiku-4-5-20251001` に解決される便利なエイリアスです。[モデルIDとバージョニング](https://platform.claude.com/docs/ja/about-claude/models/model-ids-and-versions)を参照してください。
* Claude Haiku 4.5 は、アダプティブ思考ではなく、手動の「extended thinking」（拡張思考）（`thinking.type: "enabled"`）を使用します。
* [Models API](https://platform.claude.com/docs/ja/api/models/list) を使用して、制限や機能をプログラムから照会できます。
## リソース
Claude Haiku 4.5からClaude Haiku 5.5へ移行する際の変更点。
現在のHaikuモデル：概要、仕様、リソース。
Claude Haiku 4.5は、`budget_tokens`を使用した手動の拡張思考をサポートしています。
## リファレンス
Claude Haiku 4.5 が claude.ai および Claude アプリで使用するシステムプロンプト。
Claude Haiku 4.5 の安全性評価とデプロイに関する判断。
バッチ割引やプロンプトキャッシングの料金を含む、完全な料金表。
モデルID、エイリアス、固定スナップショットの仕組み。
すべての Claude モデルのライフサイクルステータスと廃止に関するコミットメント。
Claude Haiku 4.5 は、InvokeModel による Bedrock 統合および Bedrock 形式のモデルIDでも利用できます。