claude-sonnet-5-5 — API, Pricing & Context Window | Vivgrid

claude-sonnet-5-5 is the latest model in Anthropic's Sonnet tier, offering the best combination of speed and intelligence in the Claude lineup. It keeps the 1M-token context window and 128K-token max output of claude-sonnet-5 at the same per-token price, and runs with adaptive thinking on by default.

On Vivgrid, claude-sonnet-5-5 is geo-distributed across AMER, EMEA, and APAC and reachable on both the native Messages API (/messages) and Chat Completions (/chat/completions). It uses the same unified Vivgrid API key as the rest of the catalog, so moving an agent from claude-sonnet-5 is a model-string change.

Specifications

Pricing

Pricing in USD per 1M tokens, matching the provider's rates.

What one request costs

The rates above applied to a 20K-token prompt with a 2K-token reply — a typical single agent turn, small enough that every request is billed at the base rate.

Prompt caching is billed at $2.50 per 1M cache-write tokens on the 5-minute TTL and $4.00 per 1M on the 1-hour TTL, with cached reads at $0.20.

API surfaces

The Vivgrid Console catalogs claude-sonnet-5-5 on 2 surfaces, all behind the same API key. The endpoint shown is the one the Console previews for that surface.

Quick start

Get an API key from the Vivgrid Console, then call claude-sonnet-5-5 directly.

curl https://api.vivgrid.com/v1/chat/completions \
  -H "Authorization: Bearer $VIVGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "claude-sonnet-5-5",
    "messages": [
      { "role": "user", "content": "Say hello in English, Chinese and Spanish." }
    ],
    "stream": true
  }'

curl https://api.vivgrid.com/v1/messages \
  -H "Authorization: Bearer $VIVGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "claude-sonnet-5-5",
    "max_tokens": 1024,
    "messages": [
      { "role": "user", "content": "Say hello in English, Chinese and Spanish." }
    ],
    "stream": true
  }'

Choosing within the Claude 5 family

Prices are USD per 1M tokens at the base rate. Rows marked this page are the model described here.

Ideal use cases

• Everyday coding agents balancing quality, speed, and cost
• High-volume tool-calling and agentic workflows
• Long-context analysis within a 1M-token budget
• Teams on claude-sonnet-5 upgrading at the same price

Related models

• claude-sonnet-5 — the prior Sonnet release
• claude-opus-5-5 — the latest frontier Opus model
• gpt-6.1-sol — OpenAI's latest balanced gpt-6 model