Model Comparison
DeepSeek-V2.5 vs GPT OSS 120BWhich is better in 2026?
GPT OSS 120B significantly outperforms across most benchmarks. DeepSeek-V2.5 is 1.0x cheaper per token.
Verdict: DeepSeek-V2.5 vs GPT OSS 120B — which is better?
DeepSeek-V2.5 (by DeepSeek) and GPT OSS 120B (by OpenAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.
DeepSeek-V2.5 outperforms in 0 benchmarks, while GPT OSS 120B is better at 1 benchmark (MMLU). GPT OSS 120B significantly outperforms across most benchmarks.
GPT OSS 120B also accepts a larger context window (131,072 input tokens), making it the stronger choice for long documents and large codebases.
Choose DeepSeek-V2.5 if…
- you want predictable pricing at $0.14/M input and $0.28/M output
Choose GPT OSS 120B if…
- you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
- you process long inputs — it offers a 131,072 token context window
- you want the most recent training data — it shipped Aug 2025
Performance Benchmarks
Comparative analysis across standard metrics
DeepSeek-V2.5 outperforms in 0 benchmarks, while GPT OSS 120B is better at 1 benchmark (MMLU).
GPT OSS 120B significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, DeepSeek-V2.5 ($0.14/1M tokens) is 1.6x more expensive than GPT OSS 120B ($0.09/1M tokens).
For output processing, DeepSeek-V2.5 ($0.28/1M tokens) is 1.6x cheaper than GPT OSS 120B ($0.45/1M tokens).
In conclusion, GPT OSS 120B is more expensive than DeepSeek-V2.5.*
* Using a 3:1 ratio of input to output tokens
Model Size
Parameter count comparison
DeepSeek-V2.5 has 119.2B more parameters than GPT OSS 120B, making it 102.1% larger.
Context Window
Maximum input and output token capacity
GPT OSS 120B accepts 131,072 input tokens compared to DeepSeek-V2.5's 8,192 tokens. GPT OSS 120B can generate longer responses up to 131,072 tokens, while DeepSeek-V2.5 is limited to 8,192 tokens.
License
Usage and distribution terms
DeepSeek-V2.5 is licensed under deepseek, while GPT OSS 120B uses Apache 2.0.
License differences may affect how you can use these models in commercial or open-source projects.
deepseek
Open weights
Apache 2.0
Open weights
Release Timeline
When each model was launched
DeepSeek-V2.5 was released on 2024-05-08, while GPT OSS 120B was released on 2025-08-05.
GPT OSS 120B is 15 months newer than DeepSeek-V2.5.
May 8, 2024
2.1 years ago
Aug 5, 2025
10 months ago
1.2yr newerKnowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
DeepSeek-V2.5 is available from DeepSeek, DeepInfra, Hyperbolic. GPT OSS 120B is available from DeepInfra, Novita, OpenAI, Fireworks, Groq.
DeepSeek-V2.5
GPT OSS 120B
Outputs Comparison
Key Takeaways
DeepSeek-V2.5
View detailsDeepSeek
GPT OSS 120B
View detailsOpenAI
Detailed Comparison
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FAQ
Common questions about DeepSeek-V2.5 vs GPT OSS 120B.