AI model comparison
Gemini 3.5 Flash Lite vs GPT-5.1-Codex-Mini
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite is a high-efficiency model from Google with upgraded agentic capabilities.
- Input / 1M
- $0.30
- Output / 1M
- $2.50
- Context
- 1.05M
OpenAI
GPT-5.1-Codex-Mini
GPT-5.1-Codex-Mini is a smaller and faster version of GPT-5.1-Codex
- Input / 1M
- $0.25
- Output / 1M
- $2
- Context
- 400K
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
GPT-5.1-Codex-Mini
1.2x cheaper for a typical chat
Higher intelligence score
Gemini 3.5 Flash Lite
22.2 vs 20.4 on Artificial Analysis
Larger context window
Gemini 3.5 Flash Lite
1.05M vs 400K tokens
Newer release
Gemini 3.5 Flash Lite
Released July 21, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
Gemini 3.5 Flash Lite22.2GPT-5.1-Codex-Mini20.4Coding index
Gemini 3.5 Flash Lite49.3GPT-5.1-Codex-MiniNot availableAgentic index
Gemini 3.5 Flash Lite14.3GPT-5.1-Codex-MiniNot availablePricing
Gemini 3.5 Flash Lite vs GPT-5.1-Codex-Mini API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | Gemini 3.5 Flash Lite | GPT-5.1-Codex-Mini |
|---|---|---|
| Input tokensPer 1M tokens | $0.30 | $0.25 |
| Output tokensPer 1M tokens | $2.50 | $2 |
| Cached input (read)Per 1M tokens | $0.03 | $0.03 |
| Cache writePer 1M tokens | $0.08 | Not available |
| Web searchPer request | $0.014 | $0.01 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
Gemini 3.5 Flash Lite$1.85GPT-5.1-Codex-Mini$1.50Coding task
30K in, 4K out
Gemini 3.5 Flash Lite$19$10.90 cachedGPT-5.1-Codex-Mini$15.50$8.90 cachedLong document summary
150K in, 2K out
Gemini 3.5 Flash Lite$50$9.50 cachedGPT-5.1-Codex-Mini$41.50$8.50 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | Gemini 3.5 Flash Lite | GPT-5.1-Codex-Mini |
|---|---|---|
| Context window | 1.05M tokens | 400K tokens |
| Max output | 66K tokens | 128K tokens |
| Input types | Audio, File, Image, Text, Video | Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | High, Medium, Low, Minimal | High, Medium, Low |
| Default reasoning effort | Minimal | Medium |
| Release date | July 21, 2026 | November 13, 2025 |
Features
Supported features
API features available for each model.
| Metric | Gemini 3.5 Flash Lite | GPT-5.1-Codex-Mini |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Supported | Not supported |
| Stop sequences | Supported | Not supported |
| Deterministic seed | Supported | Supported |
| Verbosity control | Not supported | Supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
Gemini 3.5 Flash LiteView full model details- Gemini 3.5 Flash Lite vs DeepSeek V4 Flash 0423
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GPT-5.1-Codex-MiniView full model details- GPT-5.1-Codex-Mini vs DeepSeek V4 Flash 0423
- GPT-5.1-Codex-Mini vs GPT-5.4 Mini
- GPT-5.1-Codex-Mini vs Nemotron 3 Ultra
- GPT-5.1-Codex-Mini vs GLM 4.7
- GPT-5.1-Codex-Mini vs Qwen3.5 397B A17B
- GPT-5.1-Codex-Mini vs GPT-5.4 Nano
- GPT-5.1-Codex-Mini vs GPT-5 Mini
- GPT-5.1-Codex-Mini vs o3
- GPT-5.1-Codex-Mini vs Step 3.7 Flash
- GPT-5.1-Codex-Mini vs GLM 4.6
Our take
GPT-5.1-Codex-Mini is 1.2x cheaper for a typical chat. Gemini 3.5 Flash Lite scores higher on the Artificial Analysis Intelligence Index (22.2 vs 20.4). Gemini 3.5 Flash Lite has the larger context window (1.05M vs 400K tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is Gemini 3.5 Flash Lite or GPT-5.1-Codex-Mini cheaper?
GPT-5.1-Codex-Mini is cheaper for a typical chat (2K input tokens and 500 output tokens). GPT-5.1-Codex-Mini costs $0.25 per 1M input tokens and $2 per 1M output tokens, while Gemini 3.5 Flash Lite costs $0.30 per 1M input tokens and $2.50 per 1M output tokens.
Which has a bigger context window, Gemini 3.5 Flash Lite or GPT-5.1-Codex-Mini?
Gemini 3.5 Flash Lite supports up to 1.05M tokens of context, compared with 400K for GPT-5.1-Codex-Mini.
Is Gemini 3.5 Flash Lite smarter than GPT-5.1-Codex-Mini?
On the Artificial Analysis Intelligence Index, Gemini 3.5 Flash Lite scores 22.2 and GPT-5.1-Codex-Mini scores 20.4, putting Gemini 3.5 Flash Lite ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use Gemini 3.5 Flash Lite and GPT-5.1-Codex-Mini at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Gemini 3.5 Flash Lite and GPT-5.1-Codex-Mini answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Gemini 3.5 Flash Lite and GPT-5.1-Codex-Mini at the same time. Compare the answers side by side and keep the best one.