Compare / head-to-head

Claude Opus 5.5vsGPT-5.6 Luna

Claude Opus 5.5 and GPT-5.6 Luna do not yet share a public benchmark, so quality cannot be compared apples-to-apples. GPT-5.6 Luna is 17.1x cheaper per token. GPT-5.6 Luna 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
GPT-5.6 Luna
17.1x cheaper, input + output
Larger context
GPT-5.6 Luna
1.1M tokens
Providers
2 providers
Anthropic · OpenAI
Claude Opus 5.5
Anthropic · released 2026-09-22
textvision
Context
1M
Max out
128K
Input /1M
$4
Output /1M
$20
Cached /1M
$0.2
Scores
9 · 1 core
GPT-5.6 Luna
OpenAI · released 2026-07-09
textvision
Context
1.1M
Max out
128K
Input /1M
$0.2
Output /1M
$1.2
Cached /1M
$0.02
Scores
8 · 6 core
Quality

Benchmark matrix

BenchmarkClaude Opus 5.5GPT-5.6 LunaΔEdge
Reported by both · 0
No public benchmark is reported for both models yet.
Only Claude Opus 5.5 reports · 9
AutomationBench 1.0.640% not reported
Chartography (with tools)89% not reported
CursorBench 4.057.8% not reported
FrontierCode v1.1 (Main)54.4% not reported
GDPval-AA v2.11846 not reported
Humanity's Last Exam (with tools)67.7% not reported
OSWorld 2.0 (partial)81.8% not reported
Terminal-Bench 4.066.4% not reported
Terminal-Bench Science 0.158.7% not reported
Only GPT-5.6 Luna reports · 7
GPQA Diamondnot reported92.3%
DeepSWE v1.1not reported67.2%
FrontierMath Tier 4 v2 (Epoch AI run)not reported61% epoch
FrontierMath Tiers 1-3 v2 (Epoch AI run)not reported82.1% epoch
OTIS Mock AIME 2024-2025 (Epoch AI run)not reported98.3% epoch
SimpleQA Verifiednot reported41% epoch
SWE-Bench Pronot reported62.7%
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 Opus 5.5 minus GPT-5.6 Luna 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 Opus 5.5GPT-5.6 LunaEdge
Context window1M tokens1.1M tokensGPT-5.6 Luna
Max output128K tokens128K tokensTie
Input price / 1M$4 $0.2 GPT-5.6 Luna
Output price / 1M$20 $1.2 GPT-5.6 Luna
Cached input / 1M$0.2 $0.02 GPT-5.6 Luna
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$24$1.4GPT-5.6 Luna
Modalitiestext · visiontext · visionTie
Released2026-09-222026-07-09
Cited benchmark scores98
Reliability

Provider status

All providers →
More matchups

Claude Opus 5.5 vs …

More matchups

GPT-5.6 Luna vs …

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Public benchmarks are a starting point. Run Claude Opus 5.5 and GPT-5.6 Luna on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.