For a standard 10M input / 2M output monthly coding workload, Claude Haiku 4.5 (20251001) costs $2.00 vs $4.00 for Claude Sonnet 5.5 (50% lower token spend).
Estimated spend for typical coding and autonomous agent workloads based on published per-token rates:
Claude Haiku 4.5 (20251001) · 10M In + 2M Out$2.00Claude Sonnet 5.5 · 10M In + 2M Out$4.00Billing ModelPrepaid · $0 Hard Stop
When to Route to Claude Haiku 4.5 (20251001) vs Claude Sonnet 5.5
Because Newton’s exposes both claude-haiku-4-5-20251001 and claude-sonnet-5-5 behind the same API key and base URL, engineering teams frequently combine both models in the same workflow: