2026-09-28T00:00:00.000ZAnthropic · NewsFor builders

Introducing Claude Sonnet 5.5

A clear upgrade over Sonnet 5 that runs 30% faster and costs up to 30% less for most work.

Why it matters

Anthropic published a model update. If you use a hosted chat, read the source before you assume your usual model changed.

What you can do

Claude Sonnet 5.5 is on the cloud board. List cost is $2 in and $10 out per million tokens.

For builders

Try Claude Sonnet 5.5. Copy the OpenRouter call.

Copy

curl https://openrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer $OPENROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"anthropic/claude-sonnet-5.5","messages":[{"role":"user","content":"Hello"}]}'

Open the source

See Claude Sonnet 5.5 Plan a job from this

Introducing Claude Sonnet 5.5

Updated just now

A clear upgrade over Sonnet 5 that runs 30% faster and costs up to 30% less for most work.

Why it matters

Anthropic published a model update. If you use a hosted chat, read the source before you assume your usual model changed.

What you can do

Claude Sonnet 5.5 is on the cloud board. List cost is $2 in and $10 out per million tokens.

For builders

Try Claude Sonnet 5.5. Copy the OpenRouter call.

Copy

curl https://openrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer $OPENROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"anthropic/claude-sonnet-5.5","messages":[{"role":"user","content":"Hello"}]}'

Open the source

See Claude Sonnet 5.5 Plan a job from this

Introducing Claude Sonnet 5.5

Why it matters

What you can do

For builders

Copy

Tags

Introducing Claude Sonnet 5.5

Why it matters

What you can do

For builders

Copy

Tags