---
title: 'Claude Haiku 5.5 API: Two-Tier Pricing, Model ID and Limits | RunAPI'
description: Call claude-haiku-5-5 on RunAPI. How the 100K-token price tier works, which tokens count toward it, 1M context, effort defaults, and API changes from Haiku 4.5.
url: https://runapi.ai/models/claude/haiku-5-5.md
canonical: https://runapi.ai/models/claude/haiku-5-5
locale: en
site: RunAPI
image: https://runapi.ai/assets/opengraph-bfaaa0f0.png
alternates:
en: https://runapi.ai/models/claude/haiku-5-5
zh-CN: https://runapi.ai/zh-CN/models/claude/haiku-5-5
es: https://runapi.ai/es/models/claude/haiku-5-5
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de: https://runapi.ai/de/models/claude/haiku-5-5
fr: https://runapi.ai/fr/models/claude/haiku-5-5
pt-BR: https://runapi.ai/pt-BR/models/claude/haiku-5-5
ko: https://runapi.ai/ko/models/claude/haiku-5-5
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nl: https://runapi.ai/nl/models/claude/haiku-5-5
pl: https://runapi.ai/pl/models/claude/haiku-5-5
tr: https://runapi.ai/tr/models/claude/haiku-5-5
zh-TW: https://runapi.ai/zh-TW/models/claude/haiku-5-5
zh-HK: https://runapi.ai/zh-HK/models/claude/haiku-5-5
ar: https://runapi.ai/ar/models/claude/haiku-5-5
x-default: https://runapi.ai/models/claude/haiku-5-5
model: Claude
provider: Anthropic
variant_id: claude-haiku-5-5
sdk_model_id: claude-haiku-5-5
modality: text
billing_unit: 1K tokens
status: active
---
> HTML version: https://runapi.ai/models/claude/haiku-5-5
> Site index for agents: https://runapi.ai/llms.txt
# claude-haiku-5-5 API
Call claude-haiku-5-5 from the Claude family through RunAPI. Billing is per token with no subscription, and a request that fails before its response starts is not charged.
**Anthropic / [Claude](https://runapi.ai/models/claude.md)**
**Operational · text · Commercial OK**
## How Claude Haiku 5.5 is billed
Anthropic released Claude Haiku 5.5 on October 7, 2026 for high-volume work such as classification, extraction, routing, summarization, and subagent tasks. It is the first Claude model priced by prompt length. When a request's prompt goes over 100,000 tokens, every rate on that request moves to a higher tier, output included. In Anthropic's list prices, each higher-tier rate is five times the short-prompt rate. The pricing table on this page lists both tiers.
RunAPI picks the tier from the whole prompt. Uncached input, cache reads, and cache writes all count toward the 100,000 tokens; output does not. A 60,000-token cached system prompt plus a 50,000-token new message adds up to 110,000 tokens, so that request pays the higher tier even though most of it is a cache read.
Haiku 5.5 uses the tokenizer introduced with Claude 4.7, which turns the same text into about 30% more tokens than Haiku 4.5 did. A prompt that stayed under 100,000 tokens on Haiku 4.5 can cross the threshold on Haiku 5.5.
On RunAPI, claude-haiku-5-5 is served through the Anthropic Messages endpoint (/v1/messages) only. RunAPI rejects requests for this model in the OpenAI Chat Completions, Responses, or Gemini formats.
**Model ID:** claude-haiku-5-5
**Released:** October 7, 2026
**Context window:** 1M tokens
**Max output:** 128K tokens
**Higher price tier:** Prompts over 100,000 tokens
**Default effort (API):** medium
**Protocol on RunAPI:** Anthropic Messages
## Try Claude Haiku 5.5
Pick any model and generate in seconds.
**Model:**
- **Message** — `message` · `claude-haiku-5-5` · Input $0.08-$0.40 / 1M tokens | Output $0.40-$2.00 / 1M tokens
**Prompt:** Describe what you want to create...
**Estimated:** Input $0.08-$0.40 / 1M tokens | Output $0.40-$2.00 / 1M tokens
- [Generate](https://runapi.ai/login)
Sign in to generate with RunAPI.
### Switch variant
- [claude-fable-5](https://runapi.ai/models/claude/fable-5.md)
- [claude-fable-5-1](https://runapi.ai/models/claude/fable-5-1.md)
- [claude-haiku-4-5-20251001](https://runapi.ai/models/claude/haiku-4-5-20251001.md)
- **claude-haiku-5-5** (current)
- [claude-opus-4-1-20250805](https://runapi.ai/models/claude/opus-4-1-20250805.md)
- [claude-opus-4-5-20251101](https://runapi.ai/models/claude/opus-4-5-20251101.md)
- [claude-opus-4-6](https://runapi.ai/models/claude/opus-4-6.md)
- [claude-opus-4-7](https://runapi.ai/models/claude/opus-4-7.md)
- [claude-opus-4-8](https://runapi.ai/models/claude/opus-4-8.md)
- [claude-opus-5](https://runapi.ai/models/claude/opus-5.md)
- [claude-opus-5-5](https://runapi.ai/models/claude/opus-5-5.md)
- [claude-sonnet-4-5-20250929](https://runapi.ai/models/claude/sonnet-4-5-20250929.md)
- [claude-sonnet-4-6](https://runapi.ai/models/claude/sonnet-4-6.md)
- [claude-sonnet-5](https://runapi.ai/models/claude/sonnet-5.md)
- [claude-sonnet-5-5](https://runapi.ai/models/claude/sonnet-5-5.md)
15 versions available
claude-haiku-5-5 is one of the Claude models on RunAPI. It uses the same API key as every other model, and you switch to it by changing the model ID in your request. Each call is synchronous and billed in USD by input, output, and cache tokens, with no subscription or minimum spend. A request that fails before the response starts is not charged; once a response is streaming, the tokens already generated are billed, even if the client disconnects.
- Per-token billing in USD with no subscription
- No charge when a request fails before its response starts
- Token-by-token streaming
- Switch models by changing one model ID
- One API key and one bill for every model and provider
## Usage metrics
- **API Calls / Day:** 3
- **Success Rate:** 66.7%
- **Avg Generation:** 1.6s
Verified customer feedback is not available for this model yet.
## Technical details
| Field | Value |
|---|---|
| Provider | Anthropic |
| Model ID | claude-haiku-5-5 |
| Modality | Text |
| Task types | Synchronous |
| API endpoint | `/v1/messages` |
| Billing unit | 1K tokens |
| Catalog status | Operational |
**HOW IT WORKS**
## Use This Model in 3 Steps
1. **Get Your Key** - Sign up for free and create an API key for claude-haiku-5-5 from the dashboard.
2. **Send a Request** - POST to /v1/messages with the claude-haiku-5-5 model slug and your parameters.
3. **Get Results** - Read the completed claude-haiku-5-5 response directly from the endpoint.
## What this model offers
- **Endpoint coverage** — Exposes 1 public endpoint(s): message.
- **Usage-based billing** — Metered by 1K tokens with no subscription requirement.
## Claude Haiku 5.5 Pricing
| Endpoint | Price |
|---|---|
| `message` | Input: $0.08-$0.40 / 1M tokens
Output: $0.40-$2.00 / 1M tokens
Prompt < 100,001 · Input: $0.08 / 1M tokens
Prompt < 100,001 · Cached input: $0.01 / 1M tokens
Prompt < 100,001 · Cache write 5m: $0.10 / 1M tokens
Prompt < 100,001 · Cache write 1h: $0.16 / 1M tokens
Prompt < 100,001 · Output: $0.40 / 1M tokens
Prompt >= 100,001 · Input: $0.40 / 1M tokens
Prompt >= 100,001 · Cached input: $0.04 / 1M tokens
Prompt >= 100,001 · Cache write 5m: $0.50 / 1M tokens
Prompt >= 100,001 · Cache write 1h: $0.80 / 1M tokens
Prompt >= 100,001 · Output: $2.00 / 1M tokens |
**API REFERENCE**
## Endpoint Specification
| Field | Value |
|---|---|
| Endpoint | `POST /v1/messages` |
| Model ID | `claude-haiku-5-5` |
| Task Types | `message` |
## Request parameters
No request parameters are published for this endpoint.
**Request example**
```json
{
"model": "claude-haiku-5-5",
"max_tokens": 1024,
"messages": [
{
"role": "user",
"content": "Review this pull request for security vulnerabilities, performance issues, and suggest concrete improvements."
}
]
}
```
### Model skill — claude-haiku-5-5
Install the skill once, then use the variant ID from this page while building.
Base URL: `https://runapi.ai`
| Endpoint | Protocol |
|---|---|
| `POST /v1/messages` | Anthropic compatible |
Use the Anthropic SDK with your RunAPI API key and `model: "claude-haiku-5-5"`.
### Use claude-haiku-5-5 with a model skill
1. **Install** — Install the model skill for the Claude line. It loads docs, request formats, and pricing notes into your coding workspace.
2. **Configure** — Point your SDK at https://runapi.ai and set your RunAPI API key. The same key works for every model and provider.
3. **Call** — Send a request in an API format this model supports, with the model field set to the model ID on this page. RunAPI forwards it to the provider.
4. **Receive** — Read the response from the same call, or stream it as it is generated. The usage field shows the tokens you are billed for.
### What's different about claude-haiku-5-5
- **VS CLAUDE-FABLE-5: 1M context; lowest-cost Claude, with higher rates above 100K-token prompts** — Mythos-class 1M context; state-of-the-art coding, reasoning, and vision
- **VS CLAUDE-FABLE-5-1: 1M context; lowest-cost Claude, with higher rates above 100K-token prompts** — 1M context; successor to Fable 5
- **VS CLAUDE-HAIKU-4-5-20251001: 1M context; lowest-cost Claude, with higher rates above 100K-token prompts** — Haiku 4.5 for reproducible outputs
## USE CASES
**Customer support**
Answer customer questions from a private knowledge base, reducing ticket volume.
**Document analysis**
Draft contract summaries and flag key clauses for attorney review.
**Code generation**
Auto-generate unit tests, code reviews, and refactoring suggestions in CI.
## Frequently asked questions about Claude Haiku 5.5
### How much does Claude Haiku 5.5 cost per million tokens?
It has two sets of rates. Prompts of up to 100,000 tokens pay the lower set, and prompts over 100,000 tokens pay the higher set for input, output, cache writes, and cache reads. In Anthropic's list prices the higher set is five times the lower one. The pricing table on this page shows RunAPI's current rates for both tiers.
### Which tokens count toward the 100,000-token threshold?
RunAPI counts the whole prompt of a request: uncached input tokens, cache reads, and cache writes. Output tokens do not count. The tier is decided per request, so one long request does not change the rate of the next short one.
### Is Haiku 5.5 really 90% cheaper than Haiku 4.5?
On short prompts, yes. Anthropic's 90% figure compares the rates for prompts up to 100,000 tokens, and prompts over that pay 50% less than Haiku 4.5. Anthropic's own estimate of the average saving is about 75%, because the new tokenizer turns the same text into roughly 30% more tokens.
### Can I use Haiku 5.5 for long agentic sessions?
It supports a 1M-token context, but once a session's prompt grows past 100,000 tokens every later request pays the higher tier. Anthropic positions Haiku 5.5 for subagents, compaction, and summarization, and recommends Sonnet 5.5 or Opus 5.5 for complex agentic coding. A Haiku subagent that gets a short, focused context stays on the lower tier.
### Can I turn thinking off on Haiku 5.5?
Yes, unlike Sonnet 5.5. thinking: {type: "disabled"} is accepted at high effort or below. The API default effort is medium and adaptive thinking is on unless you disable it. Thinking tokens count toward max_tokens, so a small max_tokens can end before any text is returned.
### What breaks when moving from Haiku 4.5 to Haiku 5.5?
Non-default temperature, top_p, or top_k values, assistant prefill, and thinking budget_tokens all return a 400. Forced tool_choice still works, but the response then starts with the tool call and has no thinking block. Thinking blocks are tied to the conversation, so keep the message history append-only.
### Can I call Claude Haiku 5.5 with the OpenAI SDK on RunAPI?
No. RunAPI serves claude-haiku-5-5 through the Anthropic Messages API only. Use the Anthropic SDK with ANTHROPIC_BASE_URL set to https://runapi.ai and your RunAPI key.
### How do I select claude-haiku-5-5?
Pass the model ID shown in the quickstart.
### What's the rate limit on this variant?
Per-key rate limits scale with your usage tier. The pricing page shows current limits. If you need higher throughput, contact support to discuss tier upgrades.
### Can I switch variants later?
Yes. Variant is a parameter in the request. Switch by changing the model ID — no code changes, no re-authentication, no separate billing setup. All variants share the same API key and request shape.
### Does it stream?
Where streaming is available, RunAPI streams end-to-end. LLM models support token-level streaming. Media models use async task polling or webhook callbacks for result delivery.
### Where do I report quality issues?
Open an issue on the public GitHub repo or email support at contact@runapi.ai. Include the task ID and model ID so the team can investigate the specific generation.
### Do I need a separate provider account?
No. Your RunAPI API key is enough to access this variant and every other model in the catalog. You do not need accounts with the underlying provider.
### RELATED
- [claude-haiku-4-5-20251001](https://runapi.ai/models/claude/haiku-4-5-20251001.md) — by Anthropic · Input $0.80 / 1M tokens | Output $4.00 / 1M tokens
- [claude-sonnet-5](https://runapi.ai/models/claude/sonnet-5.md) — by Anthropic · Input $1.60 / 1M tokens | Output $8.00 / 1M tokens
- [claude-sonnet-5-5](https://runapi.ai/models/claude/sonnet-5-5.md) — by Anthropic · Input $1.60 / 1M tokens | Output $8.00 / 1M tokens
- [claude-sonnet-4-5-20250929](https://runapi.ai/models/claude/sonnet-4-5-20250929.md) — by Anthropic · Input $2.40 / 1M tokens | Output $12.00 / 1M tokens
### Start building with Claude.
- [Create free account](https://runapi.ai/login)
- [Read the quickstart →](https://runapi.ai/docs/api/anthropic/messages)
## Building with a team?
We're here to help with enterprise setup, integrations, and technical questions.
[Contact Us](https://runapi.ai/contact.md)
---
## More from RunAPI
- [Home](https://runapi.ai/.md)
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- [RunAPI vs OpenRouter](https://runapi.ai/openrouter-alternative.md)
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- [Site index for agents](https://runapi.ai/llms.txt)
Contact: contact@runapi.ai
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"@type": "Answer",
"text": "Per-key rate limits scale with your usage tier. The pricing page shows current limits. If you need higher throughput, contact support to discuss tier upgrades."
}
},
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"name": "Can I switch variants later?",
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"@type": "Answer",
"text": "Yes. Variant is a parameter in the request. Switch by changing the model ID — no code changes, no re-authentication, no separate billing setup. All variants share the same API key and request shape."
}
},
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"name": "Does it stream?",
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}
]
```