Model comparison
Claude Sonnet 4.5 Thinking vs GPT-5 nano
Head-to-head evidence from 0 shared benchmark results across 0 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Sonnet 4.5 Thinking unranked (Not scored); GPT-5 nano #139 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Sonnet 4.5 Thinking and GPT-5 nano share 0 comparable benchmark results. 0 of 8 categories are comparable. 2 results are unique to Claude Sonnet 4.5 Thinking; 0 to GPT-5 nano.
Updated July 23, 2026- Shared results
- 0
- Claude Sonnet 4.5 Thinking only
- 2
- GPT-5 nano only
- 0
- Comparable categories
- 0 / 8
Benchmark data for Claude Sonnet 4.5 Thinking and GPT-5 nano is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 0 shared benchmark results across 0 evidence categories; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
BenchLM does not have sourced benchmark coverage for GPT-5 nano yet. This comparison is currently limited to metadata such as context window, reasoning mode, and pricing where available.
GPT-5 nano has the larger context window at 400K, compared with 200K for Claude Sonnet 4.5 Thinking.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Sonnet 4.5 Thinking | GPT-5 nano | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Sonnet 4.5 ThinkingNot available | GPT-5 nano$0.05 input / $0.4 output | A complete price comparison is not available. |
| Generation speedtokens per second | Claude Sonnet 4.5 ThinkingNot available | GPT-5 nano137 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Sonnet 4.5 ThinkingNot available | GPT-5 nano83.30 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Sonnet 4.5 Thinking200K | GPT-5 nano400K | GPT-5 nano lists the larger context window. |
Benchmark Deep Dive
Frequently Asked Questions (3)
Can I compare Claude Sonnet 4.5 Thinking and GPT-5 nano on BenchLM yet?
Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.
Why does this comparison show “coming soon”?
BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.
What data is available for Claude Sonnet 4.5 Thinking and GPT-5 nano today?
GPT-5 nano: $0.05 input / $0.40 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
Related Comparisons
Choose a model with this week’s evidence
Join 2,000+ readers for ranking moves, pricing changes, and the claims that still need proof.
One email each week. Unsubscribe anytime.