o3 Pro vs Molmo 72B
Compare o3 Pro and Molmo 72B: pricing, performance, context window, latency, and best use cases. Side-by-side comparison on XALEN.
Updated 2026-05-21 · By Abhishek Raj · Our methodology
| Feature | o3 Pro | Molmo 72B |
|---|---|---|
| Category | Reasoning | Vision |
| Parameters | ~1T | 72B |
| Context Window | 200K | 128K |
| Input Price | $0.15/1M tokens | $0.04/1M tokens |
| Output Price | $0.60/1M tokens | $0.08/1M tokens |
| Latency | ~5000ms | ~350ms |
Choose o3 Pro when:
- ✓ Research-grade reasoning
- ✓ Mathematical proofs
- ✓ Hardest problems
Deepest reasoning, Best for hard problems, Highest accuracy
Choose Molmo 72B when:
- ✓ Visual grounding
- ✓ Object detection
- ✓ Research
Fully open, Good pointing/grounding, Transparent
Verdict: o3 Pro vs Molmo 72B
For cost efficiency, Molmo 72B wins at $0.04/1M input tokens. For speed, Molmo 72B is faster at ~350ms. o3 Pro excels at Research-grade reasoning while Molmo 72B is better for Visual grounding. Both are available on XALEN through a single API — try them in the Playground to see which fits your workload.
Detailed Analysis
Pricing Comparison
o3 Pro costs $0.15/1M input tokens and $0.60/1M output tokens. Molmo 72B costs $0.04 input and $0.08 output. Molmo 72B is 3.8x cheaper on input tokens. XALEN offers batch processing at 50% discount on both models.
Performance & Context
o3 Pro has a 200K context window with ~5000ms latency. Molmo 72B offers 128K context at ~350ms. o3 Pro has the larger context window.
Best For
o3 Pro (Reasoning) is optimized for: Research-grade reasoning, Mathematical proofs, Hardest problems. Molmo 72B (Vision) works best for: Visual grounding, Object detection, Research.
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 o3 Pro
response_a = client.chat.completions.create(
model="o3-pro",
messages=[{"role": "user", "content": "Your question here"}]
)
# Use Molmo 72B
response_b = client.chat.completions.create(
model="molmo-72b",
messages=[{"role": "user", "content": "Your question here"}]
)Frequently Asked Questions
Which is better, o3 Pro or Molmo 72B?
o3 Pro (Reasoning, ~1T) offers Deepest reasoning. Molmo 72B (Vision, 72B) offers Fully open. Choose o3 Pro for Research-grade reasoning or Molmo 72B for Visual grounding.
How much does o3 Pro cost vs Molmo 72B?
o3 Pro: $0.15/1M input, $0.60/1M output. Molmo 72B: $0.04/1M input, $0.08/1M 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 o3 Pro and Molmo 72B 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.