Gemini 3.1 Pro (Preview) vs Gemini 3.5 Flash-Lite

Gemini 3.1 Pro (Preview) (Google) versus Gemini 3.5 Flash-Lite (Google): API pricing, context window, capabilities and uptime, from the same data as each model page, at the KumoAPI default channel price. Input costs 2 Credits / M for Gemini 3.1 Pro (Preview) and 0.3 Credits / M for Gemini 3.5 Flash-Lite, so Gemini 3.5 Flash-Lite is 85% cheaper. Context windows are 1M and 1M.

Gemini 3.1 Pro (Preview)gemini-3.1-pro-preview
Google
Input (prompt)
2Credits / M
Output (completion)
12Credits / M
1M context · 64K output
Gemini 3.1 Pro (Preview) details
Gemini 3.5 Flash-Litegemini-3.5-flash-lite
Google
Input (prompt)
0.3Credits / M
Output (completion)
2.5Credits / M
1M context · 64K output
Gemini 3.5 Flash-Lite details
Lower input price
Gemini 3.5 Flash-Lite
85% cheaper

Specs side by side

Item
Gemini 3.1 Pro (Preview)gemini-3.1-pro-preview
Gemini 3.5 Flash-Litegemini-3.5-flash-lite
Input (prompt) · Credits / M20.3
Output (completion) · Credits / M122.5
Cache read · Credits / M0.2—
Context window1M1M
Max output64K64K
7-day uptime——
Latest probe latency——
Measured throughput——
ProtocolsGemini generateContentGemini generateContent
Sample monthly cost (10M in + 2M out)448

Prices are the KumoAPI default channel price in Credits (1 Credit = ¥1); green marks the better side. Uptime and latency come from KumoAPI probes; a dash means the model is not probed yet.

Capabilities

CapabilityGemini 3.1 Pro (Preview)Gemini 3.5 Flash-Lite
Vision
Function Calling
Reasoning
Prompt Caching
Response Schema
Audio
Video
Streaming
File Input
Web Search
Realtime
Session
Media
Multipart Form
Binary Response

FAQ

Which is cheaper, Gemini 3.1 Pro (Preview) or Gemini 3.5 Flash-Lite?

At the KumoAPI default channel price, Gemini 3.1 Pro (Preview) input costs 2 Credits / M and Gemini 3.5 Flash-Lite input costs 0.3 Credits / M, so Gemini 3.5 Flash-Lite is 85% cheaper. Output and cache prices are in the specs table above.

Which has the larger context window, Gemini 3.1 Pro (Preview) or Gemini 3.5 Flash-Lite?

Gemini 3.1 Pro (Preview) offers 1M tokens, Gemini 3.5 Flash-Lite offers 1M tokens.

Can I switch between Gemini 3.1 Pro (Preview) and Gemini 3.5 Flash-Lite at any time?

Yes. KumoAPI calls every model with the same API key; switching is just changing the model field in the request, and billing is split per model in one console.

How do the capabilities of Gemini 3.1 Pro (Preview) and Gemini 3.5 Flash-Lite differ?

Their capability flags are identical. Every other capability is either supported by both or by neither; see the capability table above.

More comparisons

Gemini 3.1 Pro (Preview) vs Gemini 3.7 FlashGemini 3.5 Flash-Lite vs Gemini 3.7 Flash

One API key for both Gemini 3.1 Pro (Preview) and Gemini 3.5 Flash-Lite

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