Gemini 2.5 Pro vs Gemini 3.1 Flash Image

Gemini 2.5 Pro (Google) versus Gemini 3.1 Flash Image (Google): API pricing, context window, capabilities and uptime, from the same data as each model page, at the SoleAPI default channel price. Input costs 2 Credits / M for Gemini 2.5 Pro and 0.8 Credits / M for Gemini 3.1 Flash Image, so Gemini 3.1 Flash Image is 60% cheaper. Context windows are 1M and 128K.

Gemini 2.5 Progemini-2.5-pro
Google
Input (prompt)
2Credits / M
≈ $0.303
Output (completion)
16Credits / M
≈ $2.42
1M context · 64K output76% off
Gemini 2.5 Pro details
Gemini 3.1 Flash Imagegemini-3.1-flash-image
Google
Input (prompt)
0.8Credits / M
≈ $0.121
Output (completion)
4.8Credits / M
≈ $0.727
128K context · 32K output76% off
Gemini 3.1 Flash Image details
Lower input price
Gemini 3.1 Flash Image
60% cheaper
Larger context
Gemini 2.5 Pro
1M · 128K
More exclusive capabilities
Gemini 2.5 Pro
Function Calling, Prompt Caching, Response Schema

Specs side by side

Item
Gemini 2.5 Progemini-2.5-pro
Gemini 3.1 Flash Imagegemini-3.1-flash-image
Input (prompt) · Credits / M2≈ $0.3030.8≈ $0.121
Output (completion) · Credits / M16≈ $2.424.8≈ $0.727
Cache read · Credits / M0.2—
Context window1M128K
Max output64K32K
7-day uptime——
Latest probe latency——
Measured throughput60.0 t/s78.9 t/s
ProtocolsAnthropic Messages / Gemini generateContentAnthropic Messages / Gemini generateContent
Sample monthly cost (10M in + 2M out)52≈ $7.8717.6≈ $2.67

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

Capabilities

CapabilityGemini 2.5 ProGemini 3.1 Flash Image
Vision
Reasoning
Video
File Input
Streaming
Web Search
Function Calling
Prompt Caching
Response Schema
Audio
Realtime
Session
Media
Multipart Form
Binary Response

FAQ

Which is cheaper, Gemini 2.5 Pro or Gemini 3.1 Flash Image?

At the SoleAPI default channel price, Gemini 2.5 Pro input costs 2 Credits / M and Gemini 3.1 Flash Image input costs 0.8 Credits / M, so Gemini 3.1 Flash Image is 60% cheaper. Output and cache prices are in the specs table above.

Which has the larger context window, Gemini 2.5 Pro or Gemini 3.1 Flash Image?

Gemini 2.5 Pro offers 1M tokens, Gemini 3.1 Flash Image offers 128K tokens.

Can I switch between Gemini 2.5 Pro and Gemini 3.1 Flash Image at any time?

Yes. SoleAPI 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 2.5 Pro and Gemini 3.1 Flash Image differ?

Only Gemini 2.5 Pro: Function Calling, Prompt Caching, Response Schema, Audio. Every other capability is either supported by both or by neither; see the capability table above.

More comparisons

Gemini 2.5 Pro vs Gemini 2.5 FlashGemini 2.5 Pro vs Gemini 2.5 Flash ImageGemini 2.5 Pro vs Gemini 3 Flash PreviewGemini 2.5 Pro vs Gemini 3 Pro ImageGemini 2.5 Pro vs Gemini 3.1 Flash Lite ImageGemini 2.5 Pro vs Gemini 3.1 Pro PreviewGemini 2.5 Pro vs Gemini 3.7 FlashGemini 3.1 Flash Image vs Gemini 2.5 FlashGemini 3.1 Flash Image vs Gemini 2.5 Flash ImageGemini 3.1 Flash Image vs Gemini 3 Flash PreviewGemini 3.1 Flash Image vs Gemini 3 Pro ImageGemini 3.1 Flash Image vs Gemini 3.1 Flash Lite Image

One API key for both Gemini 2.5 Pro and Gemini 3.1 Flash Image

Free credits on sign-up, pay as you go, no monthly fee.

Get an API Key