Which model is better: GPT-5.6 Luna or o3-mini?

GPT-5.6 Luna is 83.6% cheaper for input tokens ($0.18 vs. $1.10 per 1M tokens) and $0.72 vs. $4.40 for output tokens (6.1x cost difference). In terms of operational performance, GPT-5.6 Luna delivers faster response latency with 90ms TTFT (1110ms faster than o3-mini). o3-mini leads coding benchmarks at 49.3% SWE-bench vs. 48.5% for GPT-5.6 Luna.
Verified daily via automated API latency tests and official documentation.

Verified Performance & Unit Economics Delta

Daily synchronized metrics from synthetic latency endpoints and benchmark evaluations.

Metric / Dimension GPT-5.6 Luna o3-mini Net Delta / Advantage
Input Cost / 1M Tokens $0.18 $1.10 GPT-5.6 Luna is 6.1x cheaper
Output Cost / 1M Tokens $0.72 $4.40 GPT-5.6 Luna (83.6% lower)
Avg TTFT Response Latency 90ms 1200ms GPT-5.6 Luna (+1110ms faster)
SWE-bench Verified (Coding) 48.5% 49.3% o3-mini (+0.8% lead)
Inference Value Score (IVR) 99.9 / 100 77 / 100 GPT-5.6 Luna (+22.9 pts)

Interactive Monthly Token Economics & ROI Forecaster

Model your expected production workload across prompt (input) and completion (output) tokens.

Live Calculation Engine
10.0M Tokens
100K 50M 250M 500M+
2.5M Tokens
100K 10M 50M 100M+

Estimated Monthly Spend

GPT-5.6 Luna $5.45

$0.18/1M in · $0.72/1M out

o3-mini $67.50

$1.1/1M in · $4.4/1M out

Projected Monthly Cost Reduction
$62.05 / mo
(91.9% lower cost)
A

When to Choose GPT-5.6 Luna

Choose GPT-5.6 Luna when you need Real-time conversational agents, high-volume classification, intent detection, and low-latency interactive apps. and have an infrastructure budget aligned with $0.18/1M tokens.

B

When to Choose o3-mini

Choose o3-mini when you need Cost-efficient STEM reasoning, high-throughput math problem-solving, and structured code synthesis. and prioritize OpenAI ecosystem integration at $1.10/1M tokens.

Related Questions & Decision Factors

Which is cheaper: GPT-5.6 Luna or o3-mini?

GPT-5.6 Luna is cheaper at $0.18/1M input tokens compared to $1.10/1M for o3-mini.

Which model has lower latency: GPT-5.6 Luna or o3-mini?

GPT-5.6 Luna delivers faster response times with an average TTFT of 90ms vs 1200ms for o3-mini.

When should you choose GPT-5.6 Luna?

Choose GPT-5.6 Luna when you need Real-time conversational agents, high-volume classification, intent detection, and low-latency interactive apps. and have an infrastructure budget aligned with $0.18/1M tokens.

When should you choose o3-mini?

Choose o3-mini when you need Cost-efficient STEM reasoning, high-throughput math problem-solving, and structured code synthesis. and prioritize OpenAI ecosystem integration at $1.10/1M tokens.

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