AI model comparison
Gemini 3.8 Flash vs Grok 4.5
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
Gemini 3.8 Flash
Gemini 3.8 Flash is Google's most intelligent Flash model with significant gains from 3.7 Flash across software engineering, agentic tasks, and multi-step reasoning.
- Input / 1M
- $0.75
- Output / 1M
- $3.75
- Context
- 1.05M
xAI
Grok 4.5
Grok 4.5 is a model from SpaceXAI with frontier performance on coding, knowledge work, and STEM.
- Input / 1M
- $2
- Output / 1M
- $6
- Context
- 500K
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Gemini 3.8 Flash
2.1x cheaper for a typical chat
Higher intelligence score
Gemini 3.8 Flash
40.9 vs 38.8 on Artificial Analysis
Larger context window
Gemini 3.8 Flash
1.05M vs 500K tokens
Newer release
Gemini 3.8 Flash
Released September 2, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
Gemini 3.8 Flash40.9Coding index
Gemini 3.8 Flash76.3Agentic index
Gemini 3.8 Flash40.2Pricing
Gemini 3.8 Flash vs Grok 4.5 API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | Gemini 3.8 Flash | |
|---|---|---|
| Input tokensPer 1M tokens | $0.75 | $2 |
| Output tokensPer 1M tokens | $3.75 | $6 |
| Cached input (read)Per 1M tokens | $0.08 | $0.30 |
| Cache writePer 1M tokens | $0.04 | Not available |
| Long-context pricingPer 1M tokens, for very long prompts | Same rate at any length | $4 in / $12 out above 200K |
| Web searchPer request | $0.014 | $0.005 |
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 3.8 Flash$3.38Coding task
30K in, 4K out
Gemini 3.8 Flash$37.50$17.25 cachedLong document summary
150K in, 2K out
Gemini 3.8 Flash$120$18.75 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | Gemini 3.8 Flash | |
|---|---|---|
| Context window | 1.05M tokens | 500K tokens |
| Max output | 66K tokens | 450K tokens |
| Input types | Audio, File, Image, Text, Video | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | High, Medium, Low | High, Medium, Low |
| Default reasoning effort | Medium | High |
| Release date | September 2, 2026 | July 8, 2026 |
Features
Supported features
API features available for each model.
| Metric | Gemini 3.8 Flash | |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Supported | Supported |
| Stop sequences | Supported | Not supported |
| Deterministic seed | Supported | Supported |
| Verbosity control | Not supported | Not supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
Gemini 3.8 FlashView full model details- Gemini 3.8 Flash vs DeepSeek V4.1 Flash
- Gemini 3.8 Flash vs GLM 5.3 Flash
- Gemini 3.8 Flash vs MiMo-V2.6-Flash
- Gemini 3.8 Flash vs Hy4 preview
- Gemini 3.8 Flash vs GPT-6 Luna
- Gemini 3.8 Flash vs DeepSeek V4 Flash 0731
- Gemini 3.8 Flash vs Claude Opus 5.5
- Gemini 3.8 Flash vs GLM 5.3
- Gemini 3.8 Flash vs DeepSeek V4 Flash 0423
- Gemini 3.8 Flash vs Step 5 Preview
- Gemini 3.8 Flash vs Hy3
- Gemini 3.8 Flash vs GPT-5.6 Luna
- Gemini 3.8 Flash vs GPT-6 Astra
- Gemini 3.8 Flash vs Kimi K3
- Gemini 3.8 Flash vs Muse Spark 1.3
- Gemini 3.8 Flash vs Grok 4.7
- Gemini 3.8 Flash vs DeepSeek V4 Pro 0813
- Gemini 3.8 Flash vs Qwen3.8 Max (0902)
- Gemini 3.8 Flash vs Grok 4.6
- Gemini 3.8 Flash vs Claude Haiku 5.5
- Gemini 3.8 Flash vs GPT-5.6 Terra
- Gemini 3.8 Flash vs Claude Sonnet 5
- Gemini 3.8 Flash vs Claude Opus 4.8
- Gemini 3.8 Flash vs Ling 3.1 Flash
- Gemini 3.8 Flash vs Claude Opus 4.7
- Gemini 3.8 Flash vs Qwen3.8 2.4T A95B
- Gemini 3.8 Flash vs Gemini 3.7 Flash
- Gemini 3.8 Flash vs Muse Spark 1.2
- Gemini 3.8 Flash vs GPT-5.4
- Gemini 3.8 Flash vs GPT-5.5
- Gemini 3.8 Flash vs Gemini 3.6 Flash
- Gemini 3.8 Flash vs Muse Spark 1.1
- Gemini 3.8 Flash vs Gemini 3.5 Flash
Our take
Gemini 3.8 Flash is 2.1x cheaper for a typical chat. Gemini 3.8 Flash scores higher on the Artificial Analysis Intelligence Index (40.9 vs 38.8). Gemini 3.8 Flash has the larger context window (1.05M vs 500K 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 3.8 Flash or Grok 4.5 cheaper?
Gemini 3.8 Flash is cheaper for a typical chat (2K input tokens and 500 output tokens). Gemini 3.8 Flash costs $0.75 per 1M input tokens and $3.75 per 1M output tokens, while Grok 4.5 costs $2 per 1M input tokens and $6 per 1M output tokens.
Which has a bigger context window, Gemini 3.8 Flash or Grok 4.5?
Gemini 3.8 Flash supports up to 1.05M tokens of context, compared with 500K for Grok 4.5.
Is Gemini 3.8 Flash smarter than Grok 4.5?
On the Artificial Analysis Intelligence Index, Gemini 3.8 Flash scores 40.9 and Grok 4.5 scores 38.8, putting Gemini 3.8 Flash ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use Gemini 3.8 Flash and Grok 4.5 at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Gemini 3.8 Flash and Grok 4.5 answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Gemini 3.8 Flash and Grok 4.5 at the same time. Compare the answers side by side and keep the best one.