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 served through the native Messages API (/messages) with geo-distributed acceleration across AMER, EMEA, and APAC. 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.

Quick start

Call claude-sonnet-5-5 through Vivgrid's unified, OpenAI-compatible endpoint. Get an API key from the Vivgrid Console.

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
  }'

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.

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