Gemini 3.1 Pro Preview vs GLM 5.1
API pricing, context window and capabilities for Gemini 3.1 Pro Preview and GLM 5.1, side by side. Prices are the cheapest serving route per 1M tokens, verified against LiteLLM and OpenRouter.
Verdict
computed from the published numbersGemini 3.1 Pro Preview wins on coding, on intelligence and on context window. GLM 5.1 wins on price.
Price
GLM 5.1
Coding
Gemini 3.1 Pro Preview
Intelligence
Gemini 3.1 Pro Preview
Context window
Gemini 3.1 Pro Preview
Key takeaways
who wins on what, from the published numbersGemini 3.1 Pro Preview wins
- Larger context window (1M vs 203K)
- More serving providers (4 vs 2)
- Supports vision
- Supports audio
- Supports structured output
- Has web search
GLM 5.1 wins
- Cheaper input ($2.00 vs $1.05 /1M)
- Cheaper output ($12.00 vs $3.50 /1M)
- Higher max output (66K vs 128K)
Cheaper overall
GLM 5.1
$1.05 + $3.50 /1M
Larger context
Gemini 3.1 Pro Preview
1M
More providers
Gemini 3.1 Pro Preview
4 providers
Pricing & specs
cheapest serving route · per 1M tokens| Gemini 3.1 Pro Preview | GLM 5.1 | |
|---|---|---|
| Input $/1M | $2.00 | $1.05 best |
| Output $/1M | $12.00 | $3.50 best |
| Context window | 1M best | 203K |
| Max output | 66K | 128K best |
| Serving providers | 4 best | 2 |
| Released | 2026-02-19 | 2026-04-07 |
Benchmarks
Artificial Analysis indices, side by side| Gemini 3.1 Pro Preview | GLM 5.1 | |
|---|---|---|
| Intelligence | 46.5 best | 40.2 |
| Coding | 68.8 best | 55.8 |
| GPQA Diamond | 94% best | 87% |
| Output speed | 154 t/s best | 91 t/s |
| Latency (TTFT) | 34.98s | 10.49s best |
Cost calculator
choose a serving route for each sideInput tokens / month
Output tokens / month
Gemini 3.1 Pro Preview
via Vertex AI
$22
GLM 5.1
via OpenRouter
$8.75
Capabilities
feature support, side by side| Feature | Gemini 3.1 Pro Preview | GLM 5.1 |
|---|---|---|
| Vision | ✓ | — |
| Tool use | ✓ | ✓ |
| Reasoning | ✓ | ✓ |
| Audio | ✓ | — |
| Prompt caching | ✓ | ✓ |
| Structured output | ✓ | — |
| Web search | ✓ | — |
Related comparisons
Frequently asked questions
Which is cheaper, Gemini 3.1 Pro Preview or GLM 5.1?
GLM 5.1 is cheaper for input ($2.00 vs $1.05 per 1M tokens). GLM 5.1 is cheaper for output ($12.00 vs $3.50 per 1M tokens).
What is the context window difference between Gemini 3.1 Pro Preview and GLM 5.1?
Gemini 3.1 Pro Preview has a 1M-token context window and GLM 5.1 has 203K tokens, so Gemini 3.1 Pro Preview can take a larger prompt.
How do Gemini 3.1 Pro Preview and GLM 5.1 compare on benchmarks?
On the tracked Artificial Analysis indices, Gemini 3.1 Pro Preview leads on coding, and Gemini 3.1 Pro Preview leads on intelligence.
Pricing verified against LiteLLM + OpenRouter + provider pages · refreshed daily
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