Claude Opus 4.1 vs Claude Sonnet 4.5
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Claude Opus 4.1
Anthropic · Aug 2025
The last $15/$75-priced Opus — a 2025 flagship now thoroughly superseded by cheaper, stronger successors.
Claude Sonnet 4.5
65.5Anthropic · Sep 2025
The model that made 30-hour autonomous coding sessions real — 77.2% SWE-bench Verified and a 1M-token context beta at $3/$15.
The verdict
Claude Sonnet 4.5 wins 1 of the 1 benchmarks these models share, against 0 for Claude Opus 4.1. On price the gap is dramatic: Claude Sonnet 4.5 works out roughly 5.0x cheaper per blended million tokens.
Benchmark head-to-head 0–1
Specs & pricing
| Claude Opus 4.1 | Claude Sonnet 4.5 | |
|---|---|---|
| modhub Index | — | 65.5 |
| Input price / 1M | $15 | $3 |
| Output price / 1M | $75 | $15 |
| Context window | 200K | 200K |
| Max output | 32K | 64K |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text, image |
| Knowledge cutoff | Mar 2025 | Jan 2025 |
| Released | Aug 2025 | Sep 2025 |
| Example monthly cost* | $262.50 | $52.50 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, Claude Opus 4.1 or Claude Sonnet 4.5?
- Claude Sonnet 4.5 wins 1 of the 1 benchmarks these models share, against 0 for Claude Opus 4.1. On price the gap is dramatic: Claude Sonnet 4.5 works out roughly 5.0x cheaper per blended million tokens.
- Which is cheaper, Claude Opus 4.1 or Claude Sonnet 4.5?
- Claude Opus 4.1 costs $15/$75 per million input/output tokens, while Claude Sonnet 4.5 costs $3/$15. For a typical workload of 10M input and 1.5M output tokens per month, that's $262.50 versus $52.50.
- Which model is better for coding, Claude Opus 4.1 or Claude Sonnet 4.5?
- On SWE-bench Verified — the standard agentic-coding benchmark — Claude Sonnet 4.5 scores 77.2% versus 74.5% for Claude Opus 4.1, making Claude Sonnet 4.5 the stronger pick for coding agents.
More comparisons
Claude Opus 4.1 vs GPT-5.5Claude Sonnet 4.5 vs GPT-5.5Claude Opus 4.1 vs GPT-5.2Claude Sonnet 4.5 vs GPT-5.2Claude Opus 4.1 vs GPT-5.1Claude Sonnet 4.5 vs GPT-5.1Claude Opus 4.1 vs GPT-5Claude Sonnet 4.5 vs GPT-5Claude Opus 4.1 vs GPT-5 miniClaude Sonnet 4.5 vs GPT-5 miniClaude Opus 4.1 vs OpenAI o3Claude Sonnet 4.5 vs OpenAI o3