Claude Sonnet 4.5 vs GPT-5 Nano
At a Glance
| Compare | Claude Sonnet 4.5Anthropic |  GPT-5 NanoOpenAI |
|---|---|---|
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $3.00Anthropic ↗ · Sep 3, 2026 | $0.025Openrouter ↗ · Sep 3, 2026 |
| Output priceFrom · USD / 1M tokens | $15.00Anthropic ↗ · Sep 3, 2026 | $0.20Openrouter ↗ · Sep 3, 2026 |
| Context windowMaximum documented tokens | 200K | 400K |
| Model facts checked | Sep 3, 2026View model evidence → | Sep 3, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
| Benchmark | Claude Sonnet 4.5 | GPT-5 Nano |
|---|---|---|
| ARC-AGI-1verified-v1-613c385b0c93 · verified_score · leader | 63.67100% of row best · percent · Claude Sonnet 4.5 (Thinking 32K) | 20.7133% of row best · percent · GPT-5 Nano (Medium) |
| ARC-AGI-2verified-v2-be40992860f9 · verified_score · leader | 13.61100% of row best · percent · Claude Sonnet 4.5 (Thinking 32K) | 2.6119% of row best · percent · GPT-5 Nano (High) |
| Berkeley Function Calling Leaderboardv4-ede5081a24bc · overall_accuracy · leader | 24.9090% of row best · percent · Claude-Sonnet-4-5-20250929 (Prompt) | 27.55100% of row best · percent · GPT-5-nano-2025-08-07 (Prompt) |
| LMArena Text Arenatext-2026-10-15-a64ca3b12b6e · arena_rating · leader | 1,434.58100% of row best · rating · claude-sonnet-4-5-20250929-high-32k; 95% CI [1431.82164426, 1437.34230911]; votes 83940; rank 88 | 1,319.9492% of row best · rating · gpt-5-nano-high; 95% CI [1313.09185399, 1326.78218151]; votes 8132; rank 232 |
| Overall ResultCounted from the protocol-matched rows above | 3 benchmark winsOverall lead | 1 benchmark win |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Side-by-Side Facts
| Field | Claude Sonnet 4.5 | GPT-5 Nano |
|---|---|---|
| Developer | Anthropic | OpenAI |
| Family | Claude 4 | Gpt 5 |
| Model | Claude Sonnet 4.5 | GPT-5 Nano |
| Version | Claude Sonnet 4.5 | GPT-5 Nano |
| Lifecycle | active | active |
| Released | 2025-09-29 | 2025-08-07 |
| Knowledge cutoff | 2025-01-01 | 2024-05-31 |
| Input modalities | Text, Image | Text, Image |
| Output modalities | Text | Text |
| Context window | 200K | 400K |
| Total parameters | Unknown | Unknown |
| Active parameters | Unknown | Unknown |
| License | Unknown | Unknown |
| Open weights | No | No |
| API available | Yes | Yes |
| Self-hostable | No | No |
| Provider access | Anthropic (Standard) | Openai (Standard), Openrouter (Standard) |
| Capabilities | chat, generation, reasoning, structured_outputs, tools | chat, generation, reasoning, structured_outputs, tools |
Claude Sonnet 4.5 Capabilities
GPT-5 Nano Capabilities
Related Comparisons
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Claude Sonnet 4.5Anthropic | vs |  Qwen3 VL FlashQwen | cross-developer peersimage, text |
Primary Evidence
Sources and Freshness
Questions
Claude Sonnet 4.5 vs GPT-5 Nano FAQs
Is Claude Sonnet 4.5 or GPT-5 Nano better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Sonnet 4.5 and GPT-5 Nano, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Claude Sonnet 4.5 or GPT-5 Nano?+
Claude Sonnet 4.5 is $3.00 and GPT-5 Nano is $0.025 per million tokens, so GPT-5 Nano is cheaper on this metric. Claude Sonnet 4.5 is $15.00 and GPT-5 Nano is $0.20 per million tokens, so GPT-5 Nano is cheaper on this metric.
Which has a larger context window, Claude Sonnet 4.5 or GPT-5 Nano?+
GPT-5 Nano has the larger sourced context window. Claude Sonnet 4.5 supports 200,000 tokens and GPT-5 Nano supports 400,000 tokens.
Which performs better in benchmarks, Claude Sonnet 4.5 or GPT-5 Nano?+
Claude Sonnet 4.5 leads the current overall benchmark count. The result uses 4 protocol-matched benchmarks from 3 publishers; it is not a universal quality score.
Can Claude Sonnet 4.5 or GPT-5 Nano be self-hosted?+
Both models have the same sourced self-hosting status: unsupported. Claude Sonnet 4.5 is not marked open weight; GPT-5 Nano is not marked open weight.
Can Claude Sonnet 4.5 and GPT-5 Nano understand images?+
Claude Sonnet 4.5 is documented with image input; GPT-5 Nano is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Claude Sonnet 4.5 or GPT-5 Nano?+
GPT-5 Nano has the larger sourced maximum output. Claude Sonnet 4.5 supports 64,000 tokens and GPT-5 Nano supports 128,000 tokens.
Do Claude Sonnet 4.5 and GPT-5 Nano support reasoning and tool use?+
Claude Sonnet 4.5: reasoning, tool calling, and image input. GPT-5 Nano: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, Claude Sonnet 4.5 or GPT-5 Nano?+
Claude Sonnet 4.5 has 1 sourced provider route; GPT-5 Nano has 2, so GPT-5 Nano has broader tracked availability.
Which offers better value, Claude Sonnet 4.5 or GPT-5 Nano?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.