Claude Opus 5 vs Claude Sonnet 5: Opus or workhorse for your Claude stack?
By TechCompare · Updated · How we check
Sonnet 5 for almost everything. Reserve Opus 5 for the hardest multi-step planning, longest-context agentic chains, or workloads where Sonnet 5's quality actually falls short and a wrong answer costs more than the extra spend on Opus.
Anthropic: Claude Opus 5
Anthropic's own price
- Input
- $5
- Output
- $25
- Cached
- $0.50
per 1M tokens
Price checked 2026-11-12
Anthropic: Claude Sonnet 5
Anthropic's own price
- Input
- $2
- Output
- $10
- Cached
- $0.20
per 1M tokens
Price checked 2026-11-12
Cost Comparison
Based on 100,000 input tokens (50% cached), 5,000 output tokens, and 100 requests.Prices come live from OpenRouter at each maker's own price where it's listed. Temporary deals are left out.
Anthropic's Claude lineup has two tiers buyers weigh against each other for almost any non-Haiku workload. Opus 5 is the deep-reasoning model, Sonnet 5 is the coding-and-agentic workhorse. Opus 5 costs about 2.5x as much as Sonnet 5 on input and 2.5x as much on output, so the real question is whether its extra depth is worth that.
The two top Claude tiers from the same lineage. Compare rates, caching, and the work each one suits.
Side-by-side specs
| Spec | Claude Opus 5 | Claude Sonnet 5 |
|---|---|---|
| Input Cost (per M) | $5.00 | $2.00 (better on this spec) |
| Output Cost (per M) | $25.00 | $10.00 (better on this spec) |
| Cached Input (per M)Cached input is text the provider has already processed. It costs less than fresh input. | $0.50 | $0.20 (better on this spec) |
| Batch input / output (per M) | $2.50 / $12.50 | $1.00 / $5.00 |
| Context Window | 1M | 1M |
How they differ
Claude Opus 5 is priced at $5.00 per million input tokens and $25.00 per million output tokens, with a 90% caching discount ($0.50 per million) and a 50% batch discount. Claude Sonnet 5 is priced at $2.00 per million input tokens and $10.00 per million output tokens, with the same 90% caching discount ($0.20 per million) and the same batch discount. Both share the 1M context window.
For a 100K input + 10K output request, Opus costs $0.75 vs Sonnet's $0.30, so Opus costs more per call. Sonnet 5's capability now covers the bulk of coding and agentic workloads that used to need Opus, which is when the Opus premium becomes hard to justify for general-purpose use.
Verdict
Reach for Opus 5 only when Sonnet 5 demonstrably stalls on hardest-tier reasoning work. Sonnet 5 is cheaper on every priced row: $2.00/M input against $5.00, $10.00/M output against $25.00, and $0.20/M cached input against $0.50. Opus 5 costs 2.5x as much on input and 2.5x as much on output. Batch takes the same share off both, and context ties at 1M. A 100K input + 10K output request costs $0.30 on Sonnet 5 against $0.75 on Opus 5, or $300,000 against $750,000 over a million calls.
Which should you pick?
Choose Claude Opus 5
Hardest-tier reasoning: long-horizon agentic planning, complex code synthesis across many files, scientific analysis. The Opus premium earns its keep only when Sonnet 5 demonstrably stalls.
Choose Claude Sonnet 5
Everyday coding, RAG, customer-facing chat, and most agentic workflows. Sonnet 5 is the new default for workloads that used to need Opus.