Synapse Garden
Anthropic · MultimodalReleased 2025-09-29

claude-sonnet-4.5

anthropic/claude-sonnet-4.5 id

Claude Sonnet 4.5 is the newest model in the Sonnet series, offering improvements and updates over Sonnet 4.

Tool useReasoningChat
Type
Use claude-sonnet-4.5
# Drop-in OpenAI-compatible client
$ import { generateText } from 'ai'
$ 
$ const { text } = await generateText({
$   model: 'anthropic/claude-sonnet-4.5',
$   baseURL: 'https://synapse.garden/api/v1',
$   apiKey: process.env.MG_KEY,
$   prompt: 'Why is the sky blue?',
$ })
1M
CONTEXT WINDOW
64K
MAX OUTPUT
$3.30/M
INPUT · PER M
$16.50/M
OUTPUT · PER M
PRICING

List prices, every modality.

RatePer million tokens · USD
Input$3.30/M
Output$16.50/M
Cache read$0.330/M
Cache write$4.13/M
Honest list pricesHow we calculate prices
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FAQ · CLAUDE-SONNET-4.5

Frequently asked

01 / 04

How do I call claude-sonnet-4.5 from my code?

Use the OpenAI or Anthropic SDK and point baseURL at https://synapse.garden/api/v1. Set model: ‘anthropic/claude-sonnet-4.5’ and supply your Synapse Garden API key. No code changes beyond the base URL.

02 / 04

How much does claude-sonnet-4.5 cost?

Input: $3.30/M per million tokens. Output: $16.50/M per million tokens. The free tier includes a million tokens every month at no cost.

03 / 04

What's the context window for claude-sonnet-4.5?

claude-sonnet-4.5 supports a context window of 1M tokens, with a maximum output of 64K tokens.

04 / 04

Do I need a separate Anthropic or OpenAI account?

No. Synapse Garden is the single API surface — one key gives you OpenAI, Anthropic, Google, Meta, Mistral, DeepSeek, xAI, Cohere, and more. Billing, rate limits, and audit logs are unified.

READY

Try claude-sonnet-4.5 in three minutes.

Sign up, create a key, drop our base URL into your existing client. The free tier includes a million tokens every month — no credit card.

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