Compare / head-to-head
GPT-5 nanovso3
o3 leads 6 of 6 shared benchmarks. GPT-5 nano is 22.2x cheaper per token. GPT-5 nano has the larger context window (400K tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
0 – 6
o3 leads
Cheaper per token
GPT-5 nano
22.2x cheaper, input + output
Larger context
GPT-5 nano
400K tokens
Provider uptime (30d)
94.2446%
OpenAI
GPT-5 nano
OpenAI · released 2025-08-07
textvision
Quality
Benchmark matrix
6 shared · 1 only GPT-5 nano · 1 only o3| Benchmark | GPT-5 nano | o3 | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 6 | ||||
| SWE-bench Verified | 54.7% ↗ | 69.1% ↗ | -14.4 pt | o3 |
| GPQA Diamond | 69.4% ↗epoch | 81.8% ↗epoch | -12.4 pt | o3 |
| AIME 2025 | 85% ↗matharena ⚠ | 89.2% ↗matharena ⚠ | -4.2 pt | o3 |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 20% ↗epoch | 33.3% ↗epoch | -13.3 pt | o3 |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 81.1% ↗epoch | 84.4% ↗epoch | -3.3 pt | o3 |
| SimpleQA Verified | 11.7% ↗epoch | 49.4% ↗epoch | -37.7 pt | o3 |
| Only GPT-5 nano reports · 1 | ||||
| FrontierMath Tier 4 v2 (Epoch AI run) | 2.4% ↗epoch | not reported | — | — |
| Only o3 reports · 1 | ||||
| SWE-bench Verified (Epoch AI run) | not reported | 62.3% ↗epoch | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is GPT-5 nano minus o3 in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | GPT-5 nano | o3 | Edge |
|---|---|---|---|
| Context window | 400K tokens | 200K tokens | GPT-5 nano |
| Max output | 128K tokens | 100K tokens | GPT-5 nano |
| Input price / 1M | $0.05 ↗ | $2 ↗ | GPT-5 nano |
| Output price / 1M | $0.4 ↗ | $8 ↗ | GPT-5 nano |
| Cached input / 1M | $0.005 ↗ | $0.5 ↗ | GPT-5 nano |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $0.45 | $10 | GPT-5 nano |
| Modalities | text · vision | text · vision | Tie |
| Released | 2025-08-07 | 2025-04-16 | — |
| Cited benchmark scores | 7 | 7 | — |
Reliability
OpenAI status
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GPT-5 nano vs …
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o3 vs …
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Which one wins on your data?
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