GPT-5.5 vs LongCat-2.5
GPT-5.5 and LongCat-2.5 are closely matched at 47.0 and 50.0 on the LLM Stats Score. LongCat-2.5 is 21.4x cheaper per token.
OpenAI · Meituan · Updated for 2026
Which is better?
GPT-5.5 and LongCat-2.5 are closely matched on the overall LLM Stats Score at 47.0 and 50.0.
In the 3 individual benchmarks reported for both models, LongCat-2.5 wins 2; this is a narrower head-to-head signal than the composite indexes.
On price, LongCat-2.5 is roughly 21.4x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.5 also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT-5.5
- you process long inputs — it offers a 1,050,000 token context window
Choose LongCat-2.5
- your work emphasizes agents — it leads those capability indexes
- you value its reported benchmark strengths — it wins 2 of 3 exact shared results
- cost matters — it's about 21.4x cheaper per token
- you want the most recent training data — it shipped Nov 2026
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
28 reported for GPT-5.5 · 23 for LongCat-2.5
GPT-5.5 outperforms in 1 benchmarks (DeepSWE 1.1), while LongCat-2.5 is better at 2 benchmarks (BrowseComp, MCP Atlas).
LongCat-2.5 shows notably better performance in the majority of benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-5.5 ($5.00/1M tokens) is 16.7x more expensive than LongCat-2.5 ($0.30/1M tokens).
For output processing, GPT-5.5 ($30.00/1M tokens) is 25.0x more expensive than LongCat-2.5 ($1.20/1M tokens).
In conclusion, GPT-5.5 is more expensive than LongCat-2.5.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.5 accepts 1,050,000 input tokens compared to LongCat-2.5's 1,048,576 tokens. LongCat-2.5 can generate longer responses up to 131,072 tokens, while GPT-5.5 is limited to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
Both GPT-5.5 and LongCat-2.5 support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-5.5
LongCat-2.5
Release Timeline
When each model was launched
GPT-5.5 was released on 2026-04-23, while LongCat-2.5 was released on 2026-11-01.
LongCat-2.5 is 6 months newer than GPT-5.5.
Apr 23, 2026
6 months ago
Nov 1, 2026
4 days ago
6mo newerKnowledge Cutoff
When training data ends
GPT-5.5 has a documented knowledge cutoff of 2025-12-01, while LongCat-2.5's cutoff date is not specified.
We can confirm GPT-5.5's training data extends to 2025-12-01, but cannot make a direct comparison without LongCat-2.5's cutoff date.
Dec 2025
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Provider Availability
GPT-5.5 is available from OpenAI. LongCat-2.5 is available from Meituan.
GPT-5.5
LongCat-2.5
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-5.5 and LongCat-2.5 side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-5.5 vs LongCat-2.5.