Compare / head-to-head

Claude Sonnet 5.5vsGPT-6 Astra

Claude Sonnet 5.5 and GPT-6 Astra do not yet share a public benchmark, so quality cannot be compared apples-to-apples. 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
0
no overlap yet
Cheaper per token
Claude Sonnet 5.5
5x cheaper, input + output
Larger context
GPT-6 Astra
1.1M tokens
Providers
2 providers
Anthropic · OpenAI
Claude Sonnet 5.5
Anthropic · released 2026-09-28
textvision
Context
1M
Max out
128K
Input /1M
$2 ↗
Output /1M
$10 ↗
Cached /1M
$0.2
Scores
6 · 1 core
GPT-6 Astra
OpenAI · released 2026-09-03
textvision
Context
1.1M
Max out
128K
Input /1M
$10 ↗
Output /1M
$50 ↗
Cached /1M
$1
Scores
8 · 5 core
Quality

Benchmark matrix

BenchmarkClaude Sonnet 5.5GPT-6 AstraΔEdge
Reported by both · 0
No public benchmark is reported for both models yet.
Only Claude Sonnet 5.5 reports · 6
Chartography (no tools)61.6% ↗not reported——
CursorBench 4.055.5% ↗not reported——
FrontierCode v1.1 (Main)46.2% ↗not reported——
Humanity's Last Exam (with tools)64.5% ↗not reported——
OSWorld 2.1 (partial)80.1% ↗not reported——
Terminal-Bench 4.070.6% ↗not reported——
Only GPT-6 Astra reports · 7
GPQA Diamondnot reported96% ↗——
AutomationBench 1.0.6not reported41.4% ↗——
FrontierMath Tier 4 v2 (Epoch AI run)not reported97.6% ↗epoch——
FrontierMath Tiers 1-3 v2 (Epoch AI run)not reported93.7% ↗epoch——
OTIS Mock AIME 2024-2025 (Epoch AI run)not reported100% ↗epoch——
SimpleQA Verifiednot reported75.6% ↗epoch——
Terminal-Bench Science 0.1not reported64.6% ↗——
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 Claude Sonnet 5.5 minus GPT-6 Astra 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

SpecClaude Sonnet 5.5GPT-6 AstraEdge
Context window1M tokens1.1M tokensGPT-6 Astra
Max output128K tokens128K tokensTie
Input price / 1M$2 ↗$10 ↗Claude Sonnet 5.5
Output price / 1M$10 ↗$50 ↗Claude Sonnet 5.5
Cached input / 1M$0.2 ↗$1 ↗Claude Sonnet 5.5
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$12$60Claude Sonnet 5.5
Modalitiestext · visiontext · visionTie
Released2026-09-282026-09-03—
Cited benchmark scores68—
Reliability

Provider status

All providers →
More matchups

Claude Sonnet 5.5 vs …

More matchups

GPT-6 Astra vs …

Built by Respan
Which one wins on your data?

Public benchmarks are a starting point. Run Claude Sonnet 5.5 and GPT-6 Astra on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.