Claude Sonnet 4

Name: Anthropic Claude Sonnet 4
Price: 3 USD
Availability: InStock
Author: Anthropic

anthropic/claude-sonnet-4

Claude Sonnet 4 significantly enhances the capabilities of its predecessor, Sonnet 3.7, excelling in both coding and reasoning tasks with improved precision and controllability. Achieving state-of-the-art performance on SWE-bench (72.7%), Sonnet 4 balances capability and computational efficiency, making it suitable for a broad range of applications from routine coding tasks to complex software development projects. Key enhancements include improved autonomous codebase navigation, reduced error rates in agent-driven workflows, and increased reliability in following intricate instructions. Sonnet 4 is optimized for practical everyday use, providing advanced reasoning capabilities while maintaining efficiency and responsiveness in diverse internal and external scenarios.

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Input price: $3.00USD / 1M tokens
Output price: $15.00USD / 1M tokens
Context window: N/A
Max output: 64K

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Prompt

Image URL or upload

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64K max outputVision

Input$3.00/MOutput$15.00/MCache read$0.30/MCache write$3.75/M

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Model card

Specifications

Pricing

Input: $3 / 1M tokens
Output: $15 / 1M tokens
Cache read: $0.30 / 1M tokens
Cache write: $3.75 / 1M tokens

Context & modalities

Max output: 64,000 tokens
Input: Text, image
Output: Text

Capabilities

Chat: Supported
Vision: Supported
Reasoning: Supported
Structured output: Not supported
Function calling: Supported
Audio input: Not supported

Access

Provider: Anthropic
Model ID: anthropic/claude-sonnet-4
Execution: sync
Base URL: https://api.sandbase.ai
API: Chat Completions API
Endpoint: /v1/chat/completions
API: Messages API
Endpoint: /v1/messages

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Production API

Chat Completions API endpoint

https://api.sandbase.ai/v1/chat/completions

Model ID

anthropic/claude-sonnet-4

# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
  -X POST "https://api.sandbase.ai/v1/chat/completions" \
  -H "Authorization: Bearer $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'SANDBASE_JSON'
{
  "model": "anthropic/claude-sonnet-4",
  "messages": [
    {
      "role": "user",
      "content": "Hello"
    }
  ],
  "max_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"

Choose your model

Compare models

All language models

Model	Context	Input / 1M	Output / 1M	Released
Claude Sonnet 4This model `Anthropic`	—	$3.00	$15.00	May 22, 2025
Claude Haiku 5.5 `Anthropic`	1M	$0.10	$0.50	Oct 7, 2026
Claude Fable 5.5 `Anthropic`	—	Coming soon	Coming soon	Coming soon
Claude Sonnet 5.5 `Anthropic`	1M	$2.00	$10.00	Sep 28, 2026
Claude Opus 5.5 `Anthropic`	1M	$4.00	$20.00	Sep 22, 2026
Claude Fable 5.1 `Anthropic`	1M	$10.00	$50.00	Sep 1, 2026

Questions

FAQ

How do I call Anthropic Claude Sonnet 4 through SandBase?

Create a SandBase API key, then send requests with the model ID "anthropic/claude-sonnet-4" to Chat Completions API (/v1/chat/completions) or Messages API (/v1/messages) at https://api.sandbase.ai. The request examples on this page show the exact payload.

How much does Anthropic Claude Sonnet 4 cost?

$3 per 1M input tokens and $15 per 1M output tokens, billed per request from your SandBase balance. Discounts, when available, are shown in the pricing on this page.

Which features does Anthropic Claude Sonnet 4 support?

Anthropic Claude Sonnet 4 supports vision (image input), reasoning, function calling. See Specifications above for the full list.

Do I need a separate Anthropic account?

No. One SandBase API key and balance gives you access to Anthropic Claude Sonnet 4 and the other models in the catalog; you do not need to sign up with Anthropic separately.