Gemini 2.5 Pro vs FLUX.1 Dev

Compare Gemini 2.5 Pro and FLUX.1 Dev: pricing, performance, context window, latency, and best use cases. Side-by-side comparison on XALEN.

Updated 2026-05-21 · By Abhishek Raj · Our methodology

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Feature Gemini 2.5 Pro FLUX.1 Dev
CategoryFrontierImage
Parameters~1.5T12B
Context Window2MN/A
Input Price$0.07/1M tokens$0.003/image/1M tokens
Output Price$0.21/1M tokensN/A/1M tokens
Latency~600ms~3s

Choose Gemini 2.5 Pro when:

  • ✓ Classical text analysis
  • ✓ Multi-document reports
  • ✓ Research
Key Strengths:

2M context, Strong multimodal, Long text analysis

Choose FLUX.1 Dev when:

  • ✓ Custom styles
  • ✓ Fine-tuned imagery
  • ✓ Development
Key Strengths:

Fine-tunable, Good quality, Open weights

Verdict: Gemini 2.5 Pro vs FLUX.1 Dev

For cost efficiency, FLUX.1 Dev wins at $0.003/image/1M input tokens. For speed, FLUX.1 Dev is faster at ~3s. Gemini 2.5 Pro excels at Classical text analysis while FLUX.1 Dev is better for Custom styles. Both are available on XALEN through a single API — try them in the Playground to see which fits your workload.

Detailed Analysis

Pricing Comparison

Gemini 2.5 Pro costs $0.07/1M input tokens and $0.21/1M output tokens. FLUX.1 Dev costs $0.003/image input and N/A output. FLUX.1 Dev is 23.3x cheaper on input tokens. XALEN offers batch processing at 50% discount on both models.

Performance & Context

Gemini 2.5 Pro has a 2M context window with ~600ms latency. FLUX.1 Dev offers N/A context at ~3s. Gemini 2.5 Pro has the larger context window.

Best For

Gemini 2.5 Pro (Frontier) is optimized for: Classical text analysis, Multi-document reports, Research. FLUX.1 Dev (Image) works best for: Custom styles, Fine-tuned imagery, Development.

Try Both on XALEN

Both models are available through XALEN's OpenAI-compatible API. Switch between them by changing the model parameter:

from xalen import XALEN

client = XALEN(api_key="xln_test_YOUR_KEY")

# Use Gemini 2.5 Pro
response_a = client.chat.completions.create(
    model="gemini-2-5-pro",
    messages=[{"role": "user", "content": "Your question here"}]
)

# Use FLUX.1 Dev
response_b = client.chat.completions.create(
    model="flux-1-dev",
    messages=[{"role": "user", "content": "Your question here"}]
)

Start Building with XALEN

200+ AI models. One API. Pay-as-you-go.

Get API Key Try in Playground

Frequently Asked Questions

Which is better, Gemini 2.5 Pro or FLUX.1 Dev?

Gemini 2.5 Pro (Frontier, ~1.5T) offers 2M context. FLUX.1 Dev (Image, 12B) offers Fine-tunable. Choose Gemini 2.5 Pro for Classical text analysis or FLUX.1 Dev for Custom styles.

How much does Gemini 2.5 Pro cost vs FLUX.1 Dev?

Gemini 2.5 Pro: $0.07/1M input, $0.21/1M output. FLUX.1 Dev: $0.003/image/1M input, N/A/1M output. Both available on XALEN with batch processing at 50% discount.

Can I use both models on XALEN?

Yes. XALEN provides 200+ models through a single OpenAI-compatible API. Switch between Gemini 2.5 Pro and FLUX.1 Dev by changing the model parameter. No code changes needed.

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Last updated: 2026-05-21. Pricing and specifications may change. Check pricing page for latest rates.