Gemini 3.1 Pro Preview vs Mercury 2
API pricing, context window and capabilities for Gemini 3.1 Pro Preview and Mercury 2, side by side. Prices are the cheapest listed serving route per 1M tokens, from LiteLLM and OpenRouter.
Verdict
computed from the published numbersGemini 3.1 Pro Preview wins on Terminal-Bench, on intelligence and on context window. Mercury 2 wins on price.
Price
Mercury 2
Terminal-Bench
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 128K)
- Higher max output (66K vs 50K)
- More serving providers (6 vs 3)
- Supports vision
- Has reasoning mode
- Supports audio
- Has web search
Mercury 2 wins
- Cheaper input ($2.00 vs $0.25 /1M)
- Cheaper output ($12.00 vs $0.75 /1M)
Cheaper overall
Mercury 2
$0.25 + $0.75 /1M
Larger context
Gemini 3.1 Pro Preview
1M
More providers
Gemini 3.1 Pro Preview
6 providers
Pricing & specs
cheapest listed route · per 1M tokensOn-demand listed rates, OpenRouter routed quotes and Vercel reseller quotes. Enterprise commitments can be materially lower.
| Gemini 3.1 Pro Preview | Mercury 2 | |
|---|---|---|
| Input $/1M | $2.00via Google | $0.25via Inception best |
| Output $/1M | $12.00via Google | $0.75via Inception best |
| Context window | 1M best | 128K |
| Max output | 66K best | 50K |
| Serving providers | 6 best | 3 |
| Date | Released Feb 19, 2026 | Released Feb 24, 2026 |
Benchmarks
Benchmark scores, side by side| Gemini 3.1 Pro Preview | Mercury 2 | |
|---|---|---|
| Intelligence | 29.7 best | 13.8 |
| Terminal-Bench | 74% best | 27% |
| GPQA Diamond | 94% best | 77% |
| Output speed | 140 t/s | 554 t/s best |
| Latency (TTFT) | 26.52s | 6.83s best |
Cost calculator
choose a serving route for each sideInput tokens / month
Output tokens / month
Gemini 3.1 Pro Preview
via Google
$22
Mercury 2
via Inception
$2.00
Capabilities
feature support, side by side| Feature | Gemini 3.1 Pro Preview | Mercury 2 |
|---|---|---|
| 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 Mercury 2?
Mercury 2 is cheaper for input ($2.00 vs $0.25 per 1M tokens) from Inception. Mercury 2 is cheaper for output ($12.00 vs $0.75 per 1M tokens) from Inception.
What is the context window difference between Gemini 3.1 Pro Preview and Mercury 2?
Gemini 3.1 Pro Preview has a 1M-token context window and Mercury 2 has 128K tokens, so Gemini 3.1 Pro Preview can take a larger prompt.
How do Gemini 3.1 Pro Preview and Mercury 2 compare on benchmarks?
On the tracked benchmarks, Gemini 3.1 Pro Preview leads on Terminal-Bench, and Gemini 3.1 Pro Preview leads on intelligence.
Listed prices from LiteLLM, OpenRouter and Vercel · last checked Oct 14, 2026
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