---
title: "Claude Opus 4.5 for OpenClaw: Pricing, Setup, and What It's Good At"
description: "Everything you need to know about using Claude Opus 4.5 with OpenClaw. Costs $5.00/M input, $25/M output. 200K context window. Here's when to use it and when to pick something else."
date: 2026-03-12
updatedDate: 2026-03-12
image: /images/models/provider-anthropic-hero.jpg
keywords: "claude opus 4.5 openclaw, claude opus 4.5 pricing, claude opus 4.5 review, anthropic openclaw, claude opus 4.5 api"
category: model-guide
modelData:
  provider: "Anthropic"
  provider_slug: "anthropic"
  full_id: "anthropic/claude-opus-4-5"
  input_cost_per_1m: 5
  output_cost_per_1m: 25
  max_input_tokens: 200000
  max_output_tokens: 64000
  features: ["function_calling", "vision", "reasoning"]
  parameter_count: null
  architecture: null
  license: null
faq:
  - question: "What are the token limits?"
    answer: "It supports a 200,000 token input context window and a 64,000 token max output limit."
  - question: "How much does it cost to run?"
    answer: "Input tokens cost $5 per million, and output tokens cost $25 per million."
---

Current as of March 2026. Opus 4.5 sits at $5/$25 input/output — same price as Opus 4.6 but without the million-token context window. That makes it a harder sell now that 4.6 exists. Still, if you need Opus-tier reasoning and 200K context is enough, it's a legitimate choice.

## Specs

| | |
|---|---|
| **Provider** | Anthropic |
| **Input cost** | $5.00 / M tokens |
| **Output cost** | $25 / M tokens |
| **Context window** | 200K tokens |
| **Max output** | 64K tokens |
| **Parameters** | N/A |
| **Features** | function_calling, vision, reasoning |

## What it's good at

#### Reliable Function Calling

It follows tool schemas more precisely than Sonnet. When your agent's execution loop keeps breaking on hallucinated arguments, stepping up to Opus-tier often fixes it without needing to debug your prompt.

#### 64K Output Buffer

Same 64K ceiling as Sonnet 4.5, so you get full code modules in a single response. Useful when you know you need the output space and the reasoning depth.

## Where it falls short

#### High Latency

Noticeably slower than the 3.5 series. Not a dealbreaker for background tasks, but interactive workflows feel sluggish.

#### Premium Pricing

$25/M output is hard to justify unless you're genuinely hitting a reasoning ceiling on Sonnet. If the task isn't breaking on logic, you're overpaying.

## Best use cases with OpenClaw

- **Complex Repository Refactoring** — Cross-file dependency reasoning is where Opus earns its price. Sonnet misses things here; Opus usually doesn't.
- **Autonomous Research Agents** — Long execution traces with many tool calls benefit from the better instruction following. Less babysitting.

## Not ideal for

- **Simple Data Extraction** — Sonnet or Haiku handle basic JSON extraction just fine for a third of the cost. Opus is overkill.
- **Real-time Chat Interfaces** — Time-to-first-token is too high. Users waiting on a support bot response will notice the lag.

## Run it through Haimaker

Skip juggling API keys. One Haimaker key gives you access to every model on the platform. Tell OpenClaw:

```
Add Haimaker as a custom provider to my OpenClaw config. Use these details:

- Provider name: haimaker
- Base URL: https://api.haimaker.ai/v1
- API key: [PASTE YOUR HAIMAKER API KEY HERE]
- API type: openai-completions

Add the auto-router model:
- haimaker/auto (reasoning: false, context: 128000, max tokens: 32000)

Create an alias "auto" for easy switching. Apply the config when done.
```

Or skip model selection entirely — Haimaker's [auto-router](/blog/openclaw-auto-router-setup/) picks the best model for each task so you don't have to.

## OpenClaw setup

Set your API key and OpenClaw handles the rest.

```bash
export ANTHROPIC_API_KEY="your-key-here"
```

That's it. OpenClaw picks up Anthropic models automatically.

## How it compares

- **vs GPT-4o** — Opus 4.5 follows complex system prompts more consistently. GPT-4o is faster and cheaper for input-heavy tasks where reasoning depth isn't the issue.
- **vs Claude 3.5 Sonnet** — Sonnet is the right daily driver for most coding tasks. Reach for Opus 4.5 only when reasoning is the actual bottleneck, not when you're just hoping a bigger model fixes a vague problem.

## Bottom line

The 'big brain' model you call when Sonnet keeps failing on the same task. Expensive and slow — that's the tradeoff. Worth it when the logic is genuinely hard; not worth it when the problem is actually in your prompt.

<a href="https://app.haimaker.ai/sign-up?utm_source=model_guide&utm_medium=cta&utm_campaign=claude-opus-4-5-openclaw" class="cta-button">TRY CLAUDE OPUS 4.5 ON HAIMAKER</a>

---

*For setup instructions, see our [API key guide](/blog/openclaw-api-key-setup). For all available models, see the [complete models guide](/blog/best-models-for-openclaw).*