Gemini 2.5 Flash-Lite vs GPT-6 Luna vs Mistral Small 3.2
Gemini 2.5 Flash-Lite comes out ahead, 85 to 78 and 64 on our weighted score, though Mistral Small 3.2 is 14% cheaper per token.
- Our pick
GoogleGemini 2.5 Flash-Lite
85/100- ECI133.9
- Price$0.10 / $0.40
- Context1.05M
OpenAIGPT-6 Luna
78/100- ECI—
- Price$0.10 / $0.50
- Context1.05M
Mistral AIMistral Small 3.2
64/100- ECI131.7
- Price$0.10 / $0.30
- Context128K
Gemini 2.5 Flash-Lite is our pick
Gemini 2.5 Flash-Lite is the better all-round choice, scoring 85/100 against GPT-6 Luna (78) and Mistral Small 3.2 (64). It leads on inputs & features. Mistral Small 3.2 wins on price. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
- CapabilityNot enough dataNo independent benchmark covers every model here yet
- Lowest priceMistral Small 3.2Mistral Small 3.2 $0.15 · Gemini 2.5 Flash-Lite $0.175 · GPT-6 Luna $0.20 per 1M tokens (3:1 blend)
- Longest contextGPT-6 Luna and Gemini 2.5 Flash-LiteGPT-6 Luna 1,050,000 · Gemini 2.5 Flash-Lite 1,048,576 · Mistral Small 3.2 128,000 tokens
- Widest inputsGemini 2.5 Flash-LiteGemini 2.5 Flash-Lite: Text, Images, PDFs, Audio, Video · GPT-6 Luna: Text, Images, PDFs · Mistral Small 3.2: Text, Images
- Self-hostingMistral Small 3.2Publishes downloadable weights
| Measure | Weight | Gemini 2.5 Flash-Lite | GPT-6 Luna | Mistral Small 3.2 |
|---|---|---|---|---|
| Price | 50% | 86 | 83 | 89 |
| Inputs & features | 30% | 100 | 80 | 50 |
| Context window | 20% | 61 | 61 | 24 |
| Overall | 100% | 85/100 | 78/100 | 64/100 |
Left out because at least one model lacks the data: capability. The remaining weights were rescaled.
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | Gemini 2.5 Flash-LiteGoogle | GPT-6 LunaOpenAI | Mistral Small 3.2Mistral AI |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 133.9 (best) | — | 131.7 |
| ECI rank | #118 of 148 (best) | — | #123 of 148 |
| GPQA DiamondGraduate-level science questions | — | 90.5% (best) | 49.1% |
| FrontierMath Tiers 1–3Research-level mathematics | — | 79.0% | — |
| OTIS Mock AIME 2024–2025Competition mathematics | — | 98.9% (best) | 30.3% |
| SimpleQA VerifiedShort factual questions | — | 41.4% | — |
| Price per million tokens | |||
| Input | $0.10 | $0.10 | $0.10 |
| Output | $0.40 | $0.50 | $0.30 (best) |
| Cached input | $0.01 | $0.01 | — |
| Blended (3:1) | $0.175 | $0.20 | $0.15 (best) |
| Long-context rate | Same rate | Over 272K: $0.20 / $0.75 | Same rate |
| Price source | Official Google API | Official OpenAI API | Official Mistral API |
| Limits | |||
| Context window | 1,048,576 tokens | 1,050,000 tokens (best) | 128,000 tokens |
| Max output | 65,536 tokens | 128,000 tokens (best) | 16,384 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | Yes |
| PDFs | Yes | Yes | No |
| Audio | Yes | No | No |
| Video | Yes | No | No |
| Reasoning | Yes | Yeslow · medium · high · xhigh · max | No |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | Yes | No |
| Availability | |||
| Weights | Proprietary | Proprietary | Open |
| API model ID | gemini-2.5-flash-lite | gpt-6-luna | mistral-small-2506 |
| API providers | 20 | 24 (best) | 6 |
| Released | Jun 17, 2025 | Sep 22, 2026 | Jun 20, 2025 |
| Knowledge cutoff | Jan 2025 | May 18, 2026 | Mar 2025 |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- Gemini 2.5 Flash-Lite$1.80
- GPT-6 Luna$2.00
- Mistral Small 3.2$1.60
Which should you choose?
Which is better: Gemini 2.5 Flash-Lite, GPT-6 Luna or Mistral Small 3.2?
Gemini 2.5 Flash-Lite is the better all-round choice, scoring 85/100 against GPT-6 Luna (78) and Mistral Small 3.2 (64). It leads on inputs & features. Mistral Small 3.2 wins on price. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
Which is cheaper, Gemini 2.5 Flash-Lite, GPT-6 Luna or Mistral Small 3.2?
Mistral Small 3.2 is cheaper at $0.10 input / $0.30 output per million tokens (official Mistral API price). Gemini 2.5 Flash-Lite costs $0.10 input / $0.40 output per million tokens (official Google API price); GPT-6 Luna costs $0.10 input / $0.50 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $0.15 per million tokens for Mistral Small 3.2 versus $0.175 for Gemini 2.5 Flash-Lite (1.2× as much) and $0.20 for GPT-6 Luna (1.3× as much).
Which scores higher on benchmarks?
There is no independent benchmark that covers all three models yet. Gemini 2.5 Flash-Lite has an ECI of 133.9, GPT-6 Luna has not been scored yet and Mistral Small 3.2 has an ECI of 131.7.
Which is better for coding?
There are no published SWE-bench Verified results for Gemini 2.5 Flash-Lite, GPT-6 Luna and Mistral Small 3.2 yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. All three support tool calling for agent workflows.
Which has the bigger context window?
GPT-6 Luna and Gemini 2.5 Flash-Lite have the largest context windows (1,050,000 and 1,048,576 tokens), against 128,000 for Mistral Small 3.2. Maximum output per response: Gemini 2.5 Flash-Lite up to 65,536, GPT-6 Luna up to 128,000, Mistral Small 3.2 up to 16,384 tokens.
Which can read images, PDFs, audio or video?
Gemini 2.5 Flash-Lite accepts text, images, PDFs, audio and video; GPT-6 Luna accepts text, images and PDFs; Mistral Small 3.2 accepts text and images. Gemini 2.5 Flash-Lite handles the widest range of inputs.
Are any of these open source?
Mistral Small 3.2 publishes its weights and can be self-hosted; Gemini 2.5 Flash-Lite and GPT-6 Luna is proprietary.
Which is newer?
GPT-6 Luna is the newest, released Sep 22, 2026. Mistral Small 3.2 came out Jun 20, 2025; Gemini 2.5 Flash-Lite came out Jun 17, 2025. Knowledge cutoff: Gemini 2.5 Flash-Lite Jan 2025, GPT-6 Luna May 18, 2026, Mistral Small 3.2 Mar 2025.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.
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