Compare / head-to-head
GPT-6 Astravs
Claude Sonnet 5.5
GPT-6 Astra leads 17 of 23 shared benchmarks. Claude Sonnet 5.5 is 5x cheaper per token. GPT-6 Astra has the larger context window (1.1M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
17 – 4
GPT-6 Astra leads · 2 tied
Cheaper per token
Claude Sonnet 5.5
5x cheaper, input + output
Larger context
GPT-6 Astra
1.1M tokens
Providers
2 providers
OpenAI · Anthropic
GPT-6 Astra
OpenAI · released 2026-09-03
textvision
Claude Sonnet 5.5
Anthropic · released 2026-09-28
textvision
Quality
Benchmark matrix
23 shared · 10 only GPT-6 Astra · 6 only Claude Sonnet 5.5| Benchmark | GPT-6 Astra | Claude Sonnet 5.5 | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 23 | ||||
| GPQA Diamond | 96% ↗ | 95.6% ↗epoch run | +0.4 pt | GPT-6 Astra |
| LMArena Elo | 1477.1 ↗ | 1471 ↗ | +6.1 | GPT-6 Astra |
| APEX-Agents (Mercor) | 64.7% ↗ | 75.5% ↗ | -10.8 pt | Claude Sonnet 5.5 |
| FrontierMath Tier 4 v2 (Epoch AI run) | 97.6% ↗epoch run | 80.5% ↗epoch run | +17.1 pt | GPT-6 Astra |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 93.7% ↗epoch run | 88.8% ↗epoch run | +4.9 pt | GPT-6 Astra |
| FrontierSWE V2 (Proximal Labs) | 65.5% ↗ | 61.9% ↗ | +3.6 pt | GPT-6 Astra |
| Furniture Assembly (Epoch AI run) | 80% ↗epoch run | 75% ↗epoch run | +5 pt | GPT-6 Astra |
| LiveBench Agentic Coding (LiveBench) | 57.3% ↗ | 56.3% ↗ | +1 pt | GPT-6 Astra |
| LiveBench Coding (LiveBench) | 80.4% ↗ | 91.4% ↗ | -11 pt | Claude Sonnet 5.5 |
| LiveBench Data Analysis (LiveBench) | 83% ↗ | 78.6% ↗ | +4.4 pt | GPT-6 Astra |
| LiveBench Instruction Following (LiveBench) | 75.6% ↗ | 70.5% ↗ | +5.1 pt | GPT-6 Astra |
| LiveBench Language (LiveBench) | 89.4% ↗ | 83.4% ↗ | +6 pt | GPT-6 Astra |
| LiveBench Mathematics (LiveBench) | 96.8% ↗ | 96.7% ↗ | +0.1 pt | GPT-6 Astra |
| LiveBench Reasoning (LiveBench) | 92.7% ↗ | 91.6% ↗ | +1.1 pt | GPT-6 Astra |
| LMArena Agent (LMArena) | 0.1227 ↗ | 0.1252 ↗ | 0 | Tie |
| LMArena Vision (LMArena) | 1284.3 ↗ | 1268.3 ↗ | +16 | GPT-6 Astra |
| LMArena WebDev (LMArena) | 1787.7 ↗ | 1786.3 ↗ | +1.4 | GPT-6 Astra |
| Mystery Game Puzzles (Epoch AI run) | 84% ↗epoch run | 65% ↗epoch run | +19 pt | GPT-6 Astra |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 100% ↗epoch run | 100% ↗epoch run | 0 | Tie |
| SAGE (Vals AI) | 46.4% ↗ | 51.8% ↗ | -5.4 pt | Claude Sonnet 5.5 |
| SimpleBench (SimpleBench) | 86.5% ↗ | 75.9% ↗ | +10.6 pt | GPT-6 Astra |
| SimpleQA Verified | 75.6% ↗epoch run | 46.5% ↗epoch run | +29.1 pt | GPT-6 Astra |
| Terminal-Bench 4.0 (Vals AI) | 59.6% ↗ | 64.1% ↗ | -4.5 pt | Claude Sonnet 5.5 |
| Only GPT-6 Astra reports · 10 | ||||
| AutomationBench 1.0.6 | 41.4% ↗ | not reported | — | — |
| BALROG (BALROG) | 68.3% ↗ | not reported | — | — |
| Chess Puzzles (Epoch AI run) | 72% ↗epoch run | not reported | — | — |
| DeepSWE v1.1 (Datacurve) | 74.1% ↗ | not reported | — | — |
| EBR-bench (Epoch AI run) | 76.2% ↗epoch run | not reported | — | — |
| GSO Opt@1 (GSO) | 77.5% ↗ | not reported | — | — |
| MirrorCode (Epoch AI run) | 46.7% ↗epoch run | not reported | — | — |
| Terminal-Bench Science 0.1 | 64.6% ↗ | not reported | — | — |
| Vending-Bench 2 (Andon Labs) | 15514.7 ↗ | not reported | — | — |
| WeirdML (Håvard Tveit Ihle) | 93.6% ↗ | not reported | — | — |
| Only Claude Sonnet 5.5 reports · 6 | ||||
| Chartography (no tools) | not reported | 61.6% ↗ | — | — |
| CursorBench 4.0 | not reported | 55.5% ↗ | — | — |
| FrontierCode v1.1 (Main) | not reported | 46.2% ↗ | — | — |
| Humanity's Last Exam (with tools) | not reported | 64.5% ↗ | — | — |
| OSWorld 2.1 (partial) | not reported | 80.1% ↗ | — | — |
| Terminal-Bench 4.0 | not reported | 70.6% ↗ | — | — |
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-6 Astra minus Claude Sonnet 5.5 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-6 Astra | Claude Sonnet 5.5 | Edge |
|---|---|---|---|
| Context window | 1.1M tokens | 1M tokens | GPT-6 Astra |
| Max output | 128K tokens | 128K tokens | Tie |
| Input price / 1M | $10 ↗ | $2 ↗ | Claude Sonnet 5.5 |
| Output price / 1M | $50 ↗ | $10 ↗ | Claude Sonnet 5.5 |
| Cached input / 1M | $1 ↗ | $0.2 ↗ | Claude Sonnet 5.5 |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $60 | $12 | Claude Sonnet 5.5 |
| Modalities | text · vision | text · vision | Tie |
| Released | 2026-09-03 | 2026-09-28 | — |
| Cited benchmark scores | 39 | 29 | — |
Reliability
Provider status
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Which one wins on your data?
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