Claude Sonnet 4.5 vs GPT-5 nano

Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.

Claude Sonnet 4.5

Anthropic · Sep 2025

65.5

The model that made 30-hour autonomous coding sessions real — 77.2% SWE-bench Verified and a 1M-token context beta at $3/$15.

GPT-5 nano

OpenAI · Aug 2025

OpenAI's cheapest model — $0.05 per million input tokens — for latency-critical routing, autocomplete and bulk tagging.

The verdict

These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: GPT-5 nano works out roughly 44x cheaper per blended million tokens. GPT-5 nano also takes 400K of context versus 200K for Claude Sonnet 4.5.

Specs & pricing

Claude Sonnet 4.5GPT-5 nano
modhub Index65.5
Input price / 1M$3$0.05
Output price / 1M$15$0.4
Context window200K400K
Max output64K128K
Open weightsnono
Reasoning modelyesyes
Multimodal inputtext, imagetext, image
Knowledge cutoffJan 2025May 2024
ReleasedSep 2025Aug 2025
Example monthly cost*$52.50$1.10

* 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 GPT-5 nano?
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: GPT-5 nano works out roughly 44x cheaper per blended million tokens. GPT-5 nano also takes 400K of context versus 200K for Claude Sonnet 4.5.
Which is cheaper, Claude Sonnet 4.5 or GPT-5 nano?
Claude Sonnet 4.5 costs $3/$15 per million input/output tokens, while GPT-5 nano costs $0.05/$0.4. For a typical workload of 10M input and 1.5M output tokens per month, that's $52.50 versus $1.10.
Which model is better for coding, Claude Sonnet 4.5 or GPT-5 nano?
We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.

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