Skip to content

Gemini 3.5 Flash (batch) vs GPT-5.6 Luna

vs
GPT-5.6 Luna

OpenAI

89#30
Signal-by-Signal Comparison
SignalGemini 3.5 Flash (batch)DeltaGPT-5.6 Luna
Capabilities
100
--
100
Benchmarks
77
-11
88
Pricing
96
-1
97
Context window size
96
0
96
Recency
100
--
100
Output Capacity
80
-5
85
Overall Result
0 wins
of 6
4 wins
GPT-5.6 Luna wins 4 of 6 signals

Score History

Score History (4 data points)
Gemini 3.5 Flash (batch)GPT-5.6 Luna
Gemini 3.5 Flash (batch)

79

current score

Leader

GPT-5.6 Luna

right now

GPT-5.6 Luna

89

current score

LMMarketCap.com
Interactive Price Comparison
100Kcalls/month
1,000tokens (~1,333 chars)
500tokens (~667 chars)

Gemini 3.5 Flash (batch)

Google

Per request$0.003000
Daily$10.00
Monthly$300.00
Annual$3600.00

GPT-5.6 Luna

OpenAI

Best Value
Per request$0.002000
Daily$6.67
Monthly$200.00
Annual$2400.00

GPT-5.6 Luna saves you $100.00/month

That's $1200.00/year compared to Gemini 3.5 Flash (batch) at your current usage level of 100K calls/month.

33% cheaper
Choose GPT-5.6 Luna for cost optimization

Gemini 3.5 Flash (batch) pricing:
Input:$0.75/M tokens
Output:$4.50/M tokens
GPT-5.6 Luna pricing:
Input:$0.50/M tokens
Output:$3.00/M tokens
Gemini 3.5 Flash (batch)

Google

79

Composite Score

Winner
GPT-5.6 Luna

OpenAI

89

Composite Score

Signal-by-Signal Comparison
MetricGemini 3.5 Flash (batch)GPT-5.6 LunaWinner
Overall Score
79
89
GPT-5.6 Luna
Rank#87#30
GPT-5.6 Luna
Quality Rank#87#30
GPT-5.6 Luna
Adoption Rank#87#30
GPT-5.6 Luna
Parameters------
Context Window1049K1050K
GPT-5.6 Luna
Pricing$0.75/$4.50/M$0.50/$3.00/M--
Signal Scores
Capabilities
100
100
Gemini 3.5 Flash (batch)
Benchmarks
77
88
GPT-5.6 Luna
Pricing
96
97
GPT-5.6 Luna
Context window size
96
96
GPT-5.6 Luna
Recency
100
100
Gemini 3.5 Flash (batch)
Output Capacity
80
85
GPT-5.6 Luna
Benchmark Head-to-Head(11 benchmarks)
Gemini 3.5: 1GPT-5.6 Luna: 0
Gemini 3.5
GPT-5.6 Luna
Normalized 0-100%
MMLU
-93%
MMLU-Pro
-84.5%
GPQA Diamond
-85%
MATH-500
-92.5%
HumanEval
-96.5%
SWE-bench Verified
-75%
IFEval
-92%
BBH
-90.5%
Arena Elo
14771465
LiveBench
-76%
HLE
-35%
Benchmark Interpretation

Our score (0-100) is driven by benchmark performance (90%) from Arena Elo ratings, MMLU, GPQA, HumanEval, SWE-bench, and 15+ standardized evaluations. Capabilities and context window serve as tiebreakers (10%). Learn more about our methodology.

Gemini 3.5 Flash (batch)Strong Performer

Scores 79/100 (rank #87), placing it in the top 70% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100
GPT-5.6 LunaElite Tier

Scores 89/100 (rank #30), placing it in the top 90% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100

GPT-5.6 Luna has a 10-point advantage, which typically translates to noticeably better performance on complex reasoning, code generation, and multi-step tasks.

When to Use Each Model

Choose Gemini 3.5 Flash (batch) when you need:

  • Step-by-step reasoning and chain-of-thought problem solving

Choose GPT-5.6 Luna when you need:

  • High-volume production workloads where API costs must be minimized
  • Step-by-step reasoning and chain-of-thought problem solving
Cost-Performance Analysis
Gemini 3.5 Flash (batch)
Input cost$0.75/M tokens
Output cost$4.50/M tokens
Cost per quality point$0.066
Est. monthly (1M tokens/day)$78.75
GPT-5.6 LunaBest Value
Input cost$0.50/M tokens
Output cost$3.00/M tokens
Cost per quality point$0.039
Est. monthly (1M tokens/day)$52.50

GPT-5.6 Luna offers 33% better value per quality point. At 1M tokens/day, you'd spend $52.50/month with GPT-5.6 Luna vs $78.75/month with Gemini 3.5 Flash (batch) - a $26.25 monthly difference.

Latency & Speed
Gemini 3.5 Flash (batch)Faster
Speed score0/100
GPT-5.6 Luna
Speed score0/100

Both models have comparable response speeds. For most applications, the latency difference is negligible.

When latency matters most: Interactive chatbots, IDE code completion, real-time translation, and user-facing applications where response time directly impacts experience. For batch processing, background summarization, or offline analysis, latency is less critical.

Example Use Cases

Code generation & review

Based on overall model capabilities and architecture for coding tasks like generating functions, debugging, and refactoring

Gemini 3.5 Flash (batch)

Customer support chatbot

Suitable for user-facing chat with competitive response times. GPT-5.6 Luna also offers lower per-token costs for high-volume support

Gemini 3.5 Flash (batch)

Long document analysis

Larger context window (1050K tokens) can process longer documents, contracts, and research papers in a single pass

GPT-5.6 Luna

Batch data extraction

Lower output pricing ($3.00/M) reduces costs when processing thousands of records daily

GPT-5.6 Luna

Creative writing & content

Higher overall composite score (89/100) correlates with better nuance, coherence, and style in long-form content

GPT-5.6 Luna

Image understanding & OCR

Supports vision input - can analyze screenshots, diagrams, photos, and scanned documents directly

Gemini 3.5 Flash (batch)
Which Should You Choose?
Our recommendation:
GPT-5.6 Luna

GPT-5.6 Luna has a moderate advantage with a 10-point lead in composite score. It wins on more signal dimensions, but Gemini 3.5 Flash (batch) has specific strengths that could make it the better choice for certain workflows.

by Google

  • Choose for Quality - Marginally better benchmark scores; both are excellent
  • Choose for Reliability - Higher uptime and faster response speeds
  • Choose for Prototyping - Stronger community support and better developer experience
  • Choose for Production - Wider enterprise adoption and proven at scale
GPT-5.6 Luna
Recommended

by OpenAI

  • Choose for Cost - 33% lower pricing; better value at scale
Capability Comparison
CapabilityGemini 3.5 Flash (batch)GPT-5.6 Luna
Vision (Image Input)
Function Calling
Streaming
JSON Mode
Reasoning
Web Search
Image Output
Monthly Cost Calculator
1,000tokens (600 in / 400 out)
100requests/day (3,000/month)

Gemini 3.5 Flash (batch)

Google

$6.75
estimated monthly cost

GPT-5.6 Luna

OpenAI

Best Value
$4.50
estimated monthly cost

GPT-5.6 Luna saves you $2.25/month

That's 33% cheaper than Gemini 3.5 Flash (batch) at 1,000 tokens/request and 100 requests/day.

Assumes 60% input / 40% output token ratio per request. Actual costs may vary based on your usage pattern.

Parameters & Context
ParameterGemini 3.5 Flash (batch)GPT-5.6 Luna
Context Window1.0M1.1M
Max Output Tokens65,536128,000
Open SourceNoNo
CreatedMay 19, 2026Jul 9, 2026
Last updated: 20m ago

Related comparisons

Gemini 3.5 Flash (batch) vs GPT-5.6 Luna (2026) | LM Market Cap