DeepSeek V4 Pro vs GPT-OSS 120B — Price, Context, and Capability Compared
Verdict
DeepSeek V4 Pro costs 2.1× more per blended million tokens than GPT-OSS 120B. GPT-OSS 120B has the larger context window (131,072 tokens). Default to GPT-OSS 120B unless you specifically need DeepSeek V4 Pro's edge.
Spec comparison
| DeepSeek V4 Pro | GPT-OSS 120B | |
|---|---|---|
| Price (input) | $0.43/M | $0.15/M ✓ |
| Price (output) | $0.87/M | $0.60/M ✓ |
| Blended price | $0.54/M | $0.26/M ✓ |
| Context window | 128,000 tokens | 131,072 tokens ✓ |
| Max output | 64,000 tokens ✓ | 32,768 tokens |
| Modalities | text | text |
| Reasoning mode | Yes | Yes |
| Released | 2026-05 | 2025-08 |
| Speed | 68 t/s | 780 t/s ✓ |
Cost at scale (3:1 blended)
| Tokens / month | DeepSeek V4 Pro | GPT-OSS 120B | Delta |
|---|---|---|---|
| 1,000,000 | $0.54 | $0.26 | $0.28 (2.1×) |
| 10,000,000 | $5.44 | $2.62 | $2.81 (2.1×) |
| 100,000,000 | $54.37 | $26.25 | $28.12 (2.1×) |
Choose DeepSeek V4 Pro if…
- ✓Thinking mode with visible chain-of-thought
- ✓Frontier-level math and competition coding
- ✓Still far cheaper than closed frontier models
- ✓Rigorous math, proofs, and hard algorithmic problems on a budget.
Choose GPT-OSS 120B if…
- ✓Open-weight MoE flagship
- ✓Ultra-fast on Groq LPUs
- ✓Strong agentic tool-use
- ✓Self-hostable or Groq-speed agentic workflows on open weights.
Run this exact matchup right now
Send the same prompt to DeepSeek V4 Pro and GPT-OSS 120B side by side and see the outputs yourself.
Try DeepSeek V4 Pro vs GPT-OSS 120B FreeFAQ
Is DeepSeek V4 Pro cheaper than GPT-OSS 120B?
GPT-OSS 120B is cheaper, at $0.26 per million blended tokens vs $0.54 for DeepSeek V4 Pro.
Which has the bigger context window, DeepSeek V4 Pro or GPT-OSS 120B?
GPT-OSS 120B has the larger context window: 131,072 tokens vs 128,000.
Can DeepSeek V4 Pro replace GPT-OSS 120B for coding?
Both are viable for coding. Thinking mode with visible chain-of-thought (DeepSeek V4 Pro) vs Open-weight MoE flagship (GPT-OSS 120B) — pick based on which strength matters more for your workload.
Which is faster, DeepSeek V4 Pro or GPT-OSS 120B?
GPT-OSS 120B is faster: 780 t/s vs 68 t/s, measured on our speed benchmarks.
Related
Pricing verified 2026-04-06. Specs verified 2026-08-08.
