Claude Sonnet 4.5 vs OpenAI o4-mini
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
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.
OpenAI o4-mini
80.9OpenAI · Apr 2025
A compact reasoning model that punched far above its price on math — 92.7% on AIME 2025 at $1.10 per million input tokens.
The verdict
Claude Sonnet 4.5 and OpenAI o4-mini split the 4 benchmarks they share evenly (2–2), so capability alone won't settle this one. On price the gap is dramatic: OpenAI o4-mini works out roughly 3.1x cheaper per blended million tokens.
Benchmark head-to-head 2–2
Specs & pricing
| Claude Sonnet 4.5 | OpenAI o4-mini | |
|---|---|---|
| modhub Index | 65.5 | 80.9 |
| Input price / 1M | $3 | $1.1 |
| Output price / 1M | $15 | $4.4 |
| Context window | 200K | 200K |
| Max output | 64K | 100K |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text, image |
| Knowledge cutoff | Jan 2025 | May 2024 |
| Released | Sep 2025 | Apr 2025 |
| Example monthly cost* | $52.50 | $17.60 |
* 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 Sonnet 4.5 or OpenAI o4-mini?
- Claude Sonnet 4.5 and OpenAI o4-mini split the 4 benchmarks they share evenly (2–2), so capability alone won't settle this one. On price the gap is dramatic: OpenAI o4-mini works out roughly 3.1x cheaper per blended million tokens.
- Which is cheaper, Claude Sonnet 4.5 or OpenAI o4-mini?
- Claude Sonnet 4.5 costs $3/$15 per million input/output tokens, while OpenAI o4-mini costs $1.1/$4.4. For a typical workload of 10M input and 1.5M output tokens per month, that's $52.50 versus $17.60.
- Which model is better for coding, Claude Sonnet 4.5 or OpenAI o4-mini?
- On SWE-bench Verified — the standard agentic-coding benchmark — Claude Sonnet 4.5 scores 77.2% versus 68.1% for OpenAI o4-mini, making Claude Sonnet 4.5 the stronger pick for coding agents.
More comparisons
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