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- Claude Opus 5.5 vs. GPT-5.6 Luna
AnthropicOpenAILLM matchup
Claude Opus 5.5vs.GPT-5.6 Luna
Which one is better?
Claude Opus 5.5 performs better than GPT-5.6 Luna, but costs 20 times (input) and 16.7 times (output) as much.
Claude Opus 5.5
Rank 1
GPT-5.6 Luna
Rank 38
Claude Opus 5.5
GPT-5.6 Luna
Claude Opus 5.5
GPT-5.6 Luna
Claude Opus 5.5
Rank 8 of 785
GPT-5.6 Luna
Rank 176 of 785
Above 272,000 tokens of context, GPT-5.6 Luna costs more: $0.40 input and $1.80 output per 1M tokens.
Choose Claude Opus 5.5 for
Choose GPT-5.6 Luna for
No clear advantage
On this page
Where is the difference?
Strengths at a glance
Opus 5.5GPT-5.6 LunaMedian of all ranked models
95 % range: Opus 5.5 121.2 to 138.7, GPT-5.6 Luna 86.4 to 105.6.
The same values and verdicts as the bars below. In the close-up the net starts at 75 points, just below the weaker model's lowest value; the reference group average is 100.
Opus 5.5 is ahead in 10 of 10 areas, GPT-5.6 Luna in none.
Opus 5.5 ahead: 10
Bar length shows the gap in index points (full width 15 points, one standard deviation of the reference group). Solid means clearly ahead, hatched not certain yet, a thin grey bar level.
Show 4 more areas that do not count toward the overall index
Bar length shows the gap in index points (full width 15 points, one standard deviation of the reference group). Solid means clearly ahead, hatched not certain yet, a thin grey bar level.
Claude Opus 5.5 vs. GPT-5.6 Luna at the same effort
Both models measured at the same reasoning efforts. This shows whether a lead comes from the model or only from more compute.
| Effort | Opus 5.5 | GPT-5.6 Luna | Gap | Verdict | Test series |
|---|---|---|---|---|---|
| max | 126.1 | 93.9 | 33.3 | Opus 5.5 ahead | 12 |
| Overall index (max vs. max) | 126.1 | 93.9 | 32.2 | Opus 5.5 ahead |
Gap and verdict compare only the Artificial Analysis test series in which both models are measured at that effort. Tied below 3 points, ahead only beyond two standard errors. The single values rest on all test series of each model, so their difference can deviate from the gap.
Which model for which task?
Everyday tasks, translated from the area values above. Each row names the values it rests on.
See for yourself: same task, one attempt
The same prompt for both models. We show the latest attempt without fixes; it does not count toward the overall index.
Claude Opus 5.5

Oct 1, 2026 · 33 s · $0.07
Test details
- Run date
- Oct 1, 2026
- API provider
- openrouter
- Requested API model
- anthropic/claude-opus-5.5
- Reasoning setting
- high
- Token limit including reasoning
- 8,192 tokens
- Output tokens
- 3,536 tokens
- Cost of the attempt
- $0.0708
- Response time
- 33.2 s
- API model reported in response
- anthropic/claude-opus-5.5
- Pinned endpoint
- Anthropic | anthropic/claude-opus-5.5-20260921
- Temperature
- Provider default
- Test protocol
- community-visual-tests-v1
- Technical checks
- Passed, not a quality rating
Visually reviewed. This individual test does not establish overall model quality.
GPT-5.6 Luna

Sep 7, 2026 · 50 s · $0.0038
Test details
- Run date
- Sep 7, 2026
- API provider
- openrouter
- Requested API model
- openai/gpt-5.6-luna
- Reasoning setting
- high
- Token limit including reasoning
- 8,192 tokens
- Output tokens
- 3,164 tokens
- Cost of the attempt
- $0.0038
- Response time
- 49.9 s
- API model reported in response
- openai/gpt-5.6-luna
- Pinned endpoint
- OpenAI | openai/gpt-5.6-luna-20260709
- Temperature
- Provider default
- Test protocol
- community-visual-tests-v1
- Technical checks
- Passed, not a quality rating
Visually reviewed. This individual test does not establish overall model quality.
SVG short test
SVG short test
One SVG task with the same fixed settings for every model, without hidden thinking.
Prompt
Return only one standalone SVG of a pelican riding a bicycle. Use viewBox="0 0 800 600", simple shapes, two clearly visible wheels and a recognizable pelican with a long beak. At most 30 SVG elements and 1800 characters. No Markdown, explanations, comments, scripts, animation, CSS or external resources.
Claude Opus 5.5
Unavailable in this round
GPT-5.6 Luna
Unavailable in this round
Claude Opus 5.5 and GPT-5.6 Luna in the overall index
Every model with a place in the overall index, both models of this matchup highlighted. You can add or hide other models.
Overall index (Gradually Meta-Score v4)
20 of 92 models
4 models in this view are measured at a lower reasoning effort than max in the overall index. Dashed column: lower reasoning effort than the top.
Popularity compared
How often the models are searched for, used and mentioned, on a scale from 0 to 100.
Claude Opus 5.5 is more popular than GPT-5.6 Luna: 68 to 45 out of 100.
Over time
Weekly values from October 18, 2026 to November 7, 2026
Claude Opus 5.5GPT-5.6 Luna
All data side by side
The better value is bold. For the overall index only when the gap is clear.
| Metric | Claude Opus 5.5 | GPT-5.6 Luna |
|---|---|---|
| Intelligence | ||
| Overall indexpoints, 100 = reference group average, higher is better | 126.1 | 93.9 |
| Rank | Rank 1 of 92 | Rank 38 of 92 |
| Price per 1M tokens | ||
| Inputwhat you send | $4 | $0.20above 272,000 tokens: $0.40 |
| Outputwhat the model writes | $20 | $1.20above 272,000 tokens: $1.80 |
| Cost per task (own tests)average of 3 original-protocol tasks both models passed (SVG short test not included) | $0.11 | $0.008 |
| Speed | ||
| Tokens per second | 106 | 94 |
| Popularity | ||
| Popularitysearch, usage and mentions, 0 to 100 | 68Rank 8 of 785 | 45Rank 176 of 785 |
| Technical | ||
| Context windowhow much text the model reads at once | 1 M tokens≈ 1,500 A4 pages | 1.05 M tokens≈ 1,580 A4 pages |
| Knowledge cutoff | June 2026 | Feb 16, 2026 |
| Released | Sep 22, 2026 | Jul 9, 2026 |
| Availability | Active | Active |
| Open weights | no | no |
Prices without caching or batch discounts · Page count as a rule of thumb from Artificial Analysis
Is there a better choice?
Overall index 96.3, rank 35$0.10 input and $0.50 output per 1M tokens
Opus 5.5 vs. GPT-6 LunaOverall index 106.6, rank 17$0.15 input and $0.60 output per 1M tokens
Opus 5.5 vs. DeepSeek V4.1 Flash 1017Shared benchmarks
Single results from the same benchmark version, task and metric. A value is bold only with the same test setup and a clear gap.
A: Claude Opus 5.5B: GPT-5.6 Luna
Show 54 more benchmarks
More comparisons
Compare Claude Opus 5.5 and GPT-5.6 Luna with the models people compare them with most often.
Compare another matchup
Predecessor and successor
The most popular comparisons
- 1Claude Opus 5.5 vs. GPT-6 Astra
- 2Claude Opus 5.5 vs. Claude Sonnet 5.5
- 3Claude Opus 5.5 vs. DeepSeek-V4-Pro
- 4Claude Opus 5.5 vs. Kimi K3.1 Pro
- 5Claude Opus 5.5 vs. Gemini 4 Argon
- 6Claude Opus 5.5 vs. Gemini 3.8 Flash
- 7Claude Opus 5.5 vs. Claude Fable 5.1
- 8Claude Opus 5.5 vs. DeepSeek-V4.1-Flash
- 9Claude Opus 5.5 vs. Qwen 3.8 Max 0902
Show all 70 comparisons
- 10Claude Opus 5.5 vs. GLM-5.3-Flash
- 11Claude Opus 5.5 vs. GPT-6.1 Sol
- 12Claude Opus 5.5 vs. Kimi K3
- 13Claude Opus 5.5 vs. Claude Sonnet 5
- 14Claude Opus 5.5 vs. Claude Haiku 5.5
- 15Claude Opus 5.5 vs. GLM-5.3
- 16Claude Opus 5.5 vs. GPT-5.6 Terra
- 17Claude Opus 5.5 vs. Gemini 3.1 Pro Preview
- 18Claude Opus 5.5 vs. Claude Opus 4.6
- 19Claude Opus 5.5 vs. Claude Sonnet 4.6
- 20Claude Opus 5.5 vs. Qwen 3.8 27B
- 21Claude Opus 5.5 vs. Grok 4.6
- 22Claude Opus 5.5 vs. GLM-5.2
- 23Claude Opus 5.5 vs. Gemini 4 Carbon
- 24Claude Opus 5.5 vs. DeepSeek V4.1 Flash 1017
- 25Claude Opus 5.5 vs. Claude Sonnet 4.5
- 26Claude Opus 5.5 vs. Muse Spark 1.3
- 27Claude Opus 5.5 vs. Claude Opus 4.8
- 28GPT-5.6 Luna vs. Gemini 3.8 Flash
- 29Claude Opus 5.5 vs. Mistral Large 4
- 30Claude Opus 5.5 vs. GPT-5.6 Sol
- 31Claude Opus 5.5 vs. GPT-5.5
- 32GPT-5.6 Luna vs. GPT-5.4 mini
- 33GPT-6.1 Sol vs. GPT-5.6 Luna
- 34Claude Opus 5.5 vs. DeepSeek-V4-Flash
- 35Claude Sonnet 5.5 vs. GPT-5.6 Luna
- 36Claude Opus 5.5 vs. Grok 4.7
- 37Claude Haiku 5.5 vs. GPT-5.6 Luna
- 38Claude Opus 5.5 vs. Mistral Large 3
- 39Claude Opus 5.5 vs. GPT-6 Luna
- 40Claude Opus 5.5 vs. Claude Opus 4.5
- 41GPT-5.6 Luna vs. DeepSeek V4.1 Flash 1017
- 42Claude Opus 5.5 vs. Claude Fable 5
- 43Claude Opus 5.5 vs. GPT-6 Sol
- 44GPT-5.6 Luna vs. DeepSeek-V4.1-Flash
- 45Claude Opus 5.5 vs. Gemini 3.6 Flash
- 46Claude Opus 5.5 vs. Mistral Medium 3.5
- 47GPT-6 Sol vs. GPT-5.6 Luna
- 48Claude Opus 5.5 vs. Muse Wonder Full
- 49GPT-5.6 Luna vs. Qwen 3.8 27B
- 50GPT-5.6 Luna vs. Grok 4.7
- 51Claude Opus 5.5 vs. Claude Haiku 4.5
- 52GPT-5.6 Luna vs. DeepSeek-V4-Flash
- 53Claude Opus 5 vs. GPT-5.6 Luna
- 54Claude Opus 5.5 vs. Gemini 3.5 Flash
- 55Claude Opus 5.5 vs. GPT-6.1 Terra
- 56Claude Opus 5.5 vs. GPT-5.4
- 57Claude Sonnet 4.5 vs. GPT-5.6 Luna
- 58Claude Opus 5.5 vs. GLM-5.1
- 59GPT-5.6 Luna vs. Gemini 3.7 Flash
- 60Claude Sonnet 5 vs. GPT-5.6 Luna
- 61GPT-5.6 Sol vs. GPT-5.6 Luna
- 62GPT-5.6 Luna vs. Gemini 3.1 Pro Preview
- 63GPT-5.6 Luna vs. GLM-5.3-Flash
- 64GPT-5.6 Luna vs. Mistral Large 4
- 65GPT-5.6 Luna vs. GPT-5.4
- 66Claude Haiku 4.5 vs. GPT-5.6 Luna
- 67GPT-5.6 Luna vs. GPT-5.5
- 68Claude Opus 4.5 vs. GPT-5.6 Luna
- 69GPT-6.1 Terra vs. GPT-5.6 Luna
- 70GPT-5.6 Luna vs. Gemini 4 Argon