GPT Luna Latest vs Step 3.5 Flash
| Signal | GPT Luna Latest | Delta | Step 3.5 Flash |
|---|---|---|---|
Capabilities | 100 | +50 | |
Pricing | 100 | 0 | |
Context window size | 96 | +10 | |
Recency | 100 | +10 | |
Output Capacity | 82 | +5 | |
Benchmarks | 0 | -66 | |
| Overall Result | 4 wins | of 6 | 2 wins |
Score History
40
current score
Step 3.5 Flash
right now
66.1
current score
GPT Luna Latest
~openai
Step 3.5 Flash
StepFun
Step 3.5 Flash saves you $10.00/month
That's $120.00/year compared to GPT Luna Latest at your current usage level of 100K calls/month.
| Metric | GPT Luna Latest | Step 3.5 Flash | Winner |
|---|---|---|---|
| Overall Score | 40 | 66 | Step 3.5 Flash |
| Rank | #256 | #189 | Step 3.5 Flash |
| Quality Rank | #256 | #189 | Step 3.5 Flash |
| Adoption Rank | #256 | #189 | Step 3.5 Flash |
| Parameters | -- | -- | -- |
| Context Window | 1050K | 262K | GPT Luna Latest |
| Pricing | $0.10/$0.50/M | $0.10/$0.30/M | -- |
| Signal Scores | |||
| Capabilities | 100 | 50 | GPT Luna Latest |
| Pricing | 100 | 100 | Step 3.5 Flash |
| Context window size | 96 | 86 | GPT Luna Latest |
| Recency | 100 | 90 | GPT Luna Latest |
| Output Capacity | 82 | 77 | GPT Luna Latest |
| Benchmarks | -- | 66 | Step 3.5 Flash |
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.
Scores 40/100 (rank #256), placing it in the top 12% of all 290 models tracked.
Scores 66/100 (rank #189), placing it in the top 35% of all 290 models tracked.
Step 3.5 Flash has a 26-point advantage, which typically translates to noticeably stronger performance on complex reasoning, code generation, and multi-step tasks.
Choose GPT Luna Latest when you need:
- Processing long documents or large codebases (1050K token context)
- Multimodal workflows that require image understanding
- Step-by-step reasoning and chain-of-thought problem solving
Choose Step 3.5 Flash when you need:
- High-volume production workloads where API costs must be minimized
- Step-by-step reasoning and chain-of-thought problem solving
- Self-hosted deployments where you need full control over the model
Step 3.5 Flash offers 33% better value per quality point. At 1M tokens/day, you'd spend $6.00/month with Step 3.5 Flash vs $9.00/month with GPT Luna Latest - a $3.00 monthly difference.
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.
Code generation & review
Based on overall model capabilities and architecture for coding tasks like generating functions, debugging, and refactoring
Customer support chatbot
Suitable for user-facing chat with competitive response times. Step 3.5 Flash also offers lower per-token costs for high-volume support
Long document analysis
Larger context window (1050K tokens) can process longer documents, contracts, and research papers in a single pass
Batch data extraction
Lower output pricing ($0.30/M) reduces costs when processing thousands of records daily
Creative writing & content
Higher overall composite score (66/100) correlates with better nuance, coherence, and style in long-form content
Image understanding & OCR
Supports vision input - can analyze screenshots, diagrams, photos, and scanned documents directly
Step 3.5 Flash clearly outperforms GPT Luna Latest with a significant 26.099999999999994-point lead. For most general use cases, Step 3.5 Flash is the stronger choice. However, GPT Luna Latest may still excel in niche scenarios.
By Use Case
Best for Quality
GPT Luna Latest
Marginally better benchmark scores; both are excellent
Best for Cost
Step 3.5 Flash
33% lower pricing; better value at scale
Best for Reliability
GPT Luna Latest
Higher uptime and faster response speeds
Best for Prototyping
GPT Luna Latest
Stronger community support and better developer experience
Best for Production
GPT Luna Latest
Wider enterprise adoption and proven at scale
by ~openai
- 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
| Capability | GPT Luna Latest | Step 3.5 Flash |
|---|---|---|
| Vision (Image Input)differs | ||
| Function Calling | ||
| Streaming | ||
| JSON Modediffers | ||
| Reasoning | ||
| Web Searchdiffers | ||
| Image Output |
GPT Luna Latest
~openai
Step 3.5 Flash
StepFun
Step 3.5 Flash saves you $0.2400/month
That's 31% cheaper than GPT Luna Latest 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.
| Parameter | GPT Luna Latest | Step 3.5 Flash |
|---|---|---|
| Context Window | 1.1M | 262K |
| Max Output Tokens | 128,000 | 65,536 |
| Open Source | No | Yes |
| Created | Sep 11, 2026 | Jan 29, 2026 |