Model Comparison
GPT OSS 120B vs LongCat-Flash-ChatWhich is better in 2026?
GPT OSS 120B significantly outperforms across most benchmarks. GPT OSS 120B is 2.9x cheaper per token.
Verdict: GPT OSS 120B vs LongCat-Flash-Chat — which is better?
GPT OSS 120B (by OpenAI) and LongCat-Flash-Chat (by Meituan) 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.
GPT OSS 120B outperforms in 2 benchmarks (GPQA, MMLU), while LongCat-Flash-Chat is better at 0 benchmarks. GPT OSS 120B significantly outperforms across most benchmarks.
On price, GPT OSS 120B is roughly 2.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
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 GPT OSS 120B if…
- you want the strongest raw capability — it leads on 2 of 2 shared benchmarks
- cost matters — it's about 2.9x cheaper per token
- you process long inputs — it offers a 131,072 token context window
Choose LongCat-Flash-Chat if…
- you want the most recent training data — it shipped Aug 2025
Performance Benchmarks
Comparative analysis across standard metrics
GPT OSS 120B outperforms in 2 benchmarks (GPQA, MMLU), while LongCat-Flash-Chat is better at 0 benchmarks.
GPT OSS 120B significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, GPT OSS 120B ($0.09/1M tokens) is 3.3x cheaper than LongCat-Flash-Chat ($0.30/1M tokens).
For output processing, GPT OSS 120B ($0.45/1M tokens) is 2.7x cheaper than LongCat-Flash-Chat ($1.20/1M tokens).
In conclusion, LongCat-Flash-Chat is more expensive than GPT OSS 120B.*
* Using a 3:1 ratio of input to output tokens
Model Size
Parameter count comparison
LongCat-Flash-Chat has 443.2B more parameters than GPT OSS 120B, making it 379.5% larger.
Context Window
Maximum input and output token capacity
GPT OSS 120B accepts 131,072 input tokens compared to LongCat-Flash-Chat's 128,000 tokens. GPT OSS 120B can generate longer responses up to 131,072 tokens, while LongCat-Flash-Chat is limited to 128,000 tokens.
License
Usage and distribution terms
GPT OSS 120B is licensed under Apache 2.0, while LongCat-Flash-Chat uses MIT.
License differences may affect how you can use these models in commercial or open-source projects.
Apache 2.0
Open weights
MIT
Open weights
Release Timeline
When each model was launched
GPT OSS 120B was released on 2025-08-05, while LongCat-Flash-Chat was released on 2025-08-29.
LongCat-Flash-Chat is 1 month newer than GPT OSS 120B.
Aug 5, 2025
1.0 years ago
Aug 29, 2025
11 months ago
3w newerKnowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
GPT OSS 120B is available from DeepInfra, Novita, OpenAI, Fireworks, Groq. LongCat-Flash-Chat is available from Meituan.
GPT OSS 120B
LongCat-Flash-Chat
Outputs Comparison
Key Takeaways
GPT OSS 120B
View detailsOpenAI
No standout differentiators in the data we have for this pair.
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against GPT OSS 120B and LongCat-Flash-Chat side-by-side, then vote on the output you prefer.
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FAQ
Common questions about GPT OSS 120B vs LongCat-Flash-Chat.