InternLM 2.5 20B vs FLUX 1.1 Pro Ultra

Compare InternLM 2.5 20B and FLUX 1.1 Pro Ultra: pricing, performance, context window, latency, and best use cases. Side-by-side comparison on XALEN.

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

All Shanghai AI Lab models All Black Forest Labs models What is an LLM API? Python Quickstart What is inference?
Feature InternLM 2.5 20B FLUX 1.1 Pro Ultra
CategoryOpen SourceImage
Parameters20B~30B
Context Window256KN/A
Input Price$0.02/1M tokens$0.06/image/1M tokens
Output Price$0.04/1M tokensN/A/1M tokens
Latency~180ms~6s

Choose InternLM 2.5 20B when:

  • ✓ Long context tasks
  • ✓ Research
  • ✓ Multilingual
Key Strengths:

256K context, Strong reasoning, Good multilingual

Choose FLUX 1.1 Pro Ultra when:

  • ✓ Print-quality imagery
  • ✓ Ultra-HD content
  • ✓ Professional art
Key Strengths:

Ultra quality, 4K output, Best detail

Verdict: InternLM 2.5 20B vs FLUX 1.1 Pro Ultra

For cost efficiency, InternLM 2.5 20B wins at $0.02/1M input tokens. For speed, InternLM 2.5 20B is faster at ~180ms. InternLM 2.5 20B excels at Long context tasks while FLUX 1.1 Pro Ultra is better for Print-quality imagery. Both are available on XALEN through a single API — try them in the Playground to see which fits your workload.

Detailed Analysis

Pricing Comparison

InternLM 2.5 20B costs $0.02/1M input tokens and $0.04/1M output tokens. FLUX 1.1 Pro Ultra costs $0.06/image input and N/A output. InternLM 2.5 20B is 3.0x cheaper on input tokens. XALEN offers batch processing at 50% discount on both models.

Performance & Context

InternLM 2.5 20B has a 256K context window with ~180ms latency. FLUX 1.1 Pro Ultra offers N/A context at ~6s. InternLM 2.5 20B has the larger context window.

Best For

InternLM 2.5 20B (Open Source) is optimized for: Long context tasks, Research, Multilingual. FLUX 1.1 Pro Ultra (Image) works best for: Print-quality imagery, Ultra-HD content, Professional art.

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 InternLM 2.5 20B
response_a = client.chat.completions.create(
    model="internlm-2-5-20b",
    messages=[{"role": "user", "content": "Your question here"}]
)

# Use FLUX 1.1 Pro Ultra
response_b = client.chat.completions.create(
    model="flux-1-1-pro-ultra",
    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, InternLM 2.5 20B or FLUX 1.1 Pro Ultra?

InternLM 2.5 20B (Open Source, 20B) offers 256K context. FLUX 1.1 Pro Ultra (Image, ~30B) offers Ultra quality. Choose InternLM 2.5 20B for Long context tasks or FLUX 1.1 Pro Ultra for Print-quality imagery.

How much does InternLM 2.5 20B cost vs FLUX 1.1 Pro Ultra?

InternLM 2.5 20B: $0.02/1M input, $0.04/1M output. FLUX 1.1 Pro Ultra: $0.06/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 InternLM 2.5 20B and FLUX 1.1 Pro Ultra by changing the model parameter. No code changes needed.

Related Comparisons

InternLM 2.5 20B vs DALL-E 3 InternLM 2.5 20B vs Gemma 3 27B InternLM 2.5 20B vs Imagen 3 InternLM 2.5 20B vs Llama 4 Scout InternLM 2.5 20B vs Llama 4 Maverick InternLM 2.5 20B vs Llama 3.3 70B

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