Anthropic: Claude Opus 4.5 API Price, Cost Calculator & Specs

Claude Opus 4.5 sits in an awkward middle ground that most teams won't actually need. At $5 input/$25 output per million tokens, you're paying 5x more than Sonnet 4.5 for reasoning that may not justify the cost difference in real applications.

The 200K context window is the real story here. Unlike Sonnet 4.5's 1M context, 200K is actually usable in production without breaking the bank. You can analyze a substantial codebase or process complex documents without triggering the massive token costs that come with 1M+ context models. For most teams, this hits the sweet spot between capability and cost.

The price premium forces you to be surgical about usage. This isn't a model you call for routine tasks. It's for problems where the cost of failure exceeds the API costs—complex architectural decisions, critical bug analysis, or situations where you need reliable step-by-step reasoning without the token bloat of "thinking" modes.

When It Makes Sense:

Architecture Analysis for Mid-Sized Codebases: If you're working with 50K-150K lines of code across multiple services, the 200K context actually fits your needs without requiring aggressive context management. The cost is high, but you're not paying for unused context like you would with 1M models.

Production Incident Debugging: When your production system is down and you need to trace through logs, configurations, and recent code changes to find the root cause, Opus 4.5's reasoning depth can save hours of manual analysis. The debugging time saved justifies the API cost.

Complex Compliance Reviews: For regulated industries where missing a detail could result in significant fines, the model's thoroughness in analyzing documentation, code, and regulatory requirements provides value beyond its raw token cost.

Multi-Service Integration Planning: When designing how multiple services should interact, you need to understand dependencies, data flows, and potential failure modes across services. The 200K context handles this scope efficiently.