The AI arena is free today

Open Superagent

LongCat-2.5 vs Seed 1.8

LongCat-2.5 leads the LLM Stats Score 50.0 to 33.6. LongCat-2.5 is 1.3x cheaper per token.

Meituan · ByteDance · Updated for 2026

Which is better?

LongCat-2.5 leads the overall LLM Stats Score 50.0 to 33.6, ranking #20 overall.

In the 4 individual benchmarks reported for both models, LongCat-2.5 wins 4; this is a narrower head-to-head signal than the composite indexes.

On price, LongCat-2.5 is roughly 1.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

LongCat-2.5 also accepts a larger context window (1,048,576 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 LongCat-2.5

  • overall performance matters — it scores 50.0 and ranks #20 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 4 of 4 exact shared results
  • cost matters — it's about 1.3x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Nov 2026

Choose Seed 1.8

  • you want predictable pricing at $0.25/M input and $2.00/M output

At a glance

The differences that matter most.

LongCat-2.5
Meituan
Seed 1.8
ByteDance
Core performance indexes
LLM Stats Score
50.0
#20
33.6
#122
Reasoning
48.3
#21
33.0
#123
Coding
38.6
#27
19.8
#125
Agents
36.3
#23
14.3
#120
Cost, coverage & limits
Benchmark wins
4 of 4
0 of 4
Input price
$0.30 / M
$0.25 / M
Output price
$1.20 / M
$2.00 / M
Context window
1,048,576
256,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
LongCat-2.5
Seed 1.8
Math
37.2#37
32.1#67
Vision
32.5#29
24.2#72
Tool use
30.2#15
6.3#176
Multimodal
34.8#15
26.9#54
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

23 reported for LongCat-2.5 · 57 for Seed 1.8

4 shared

LongCat-2.5 outperforms in 4 benchmarks (BrowseComp, CharXiv-R, Humanity's Last Exam (with tools, text-only), MathVision), while Seed 1.8 is better at 0 benchmarks.

LongCat-2.5 significantly outperforms across most benchmarks.

Mon Nov 02 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

LongCat-2.5 costs less

For input processing, LongCat-2.5 ($0.30/1M tokens) is 1.2x more expensive than Seed 1.8 ($0.25/1M tokens).

For output processing, LongCat-2.5 ($1.20/1M tokens) is 1.7x cheaper than Seed 1.8 ($2.00/1M tokens).

In conclusion, Seed 1.8 is more expensive than LongCat-2.5.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Mon Nov 02 2026 • llm-stats.com
Meituan
LongCat-2.5
Input tokens$0.30
Output tokens$1.20
Best providerMeituan
ByteDance
Seed 1.8
Input tokens$0.25
Output tokens$2.00
Best providerDeepinfra
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

LongCat-2.5 accepts 1,048,576 input tokens compared to Seed 1.8's 256,000 tokens. Seed 1.8 can generate longer responses up to 256,000 tokens, while LongCat-2.5 is limited to 131,072 tokens.

Meituan
LongCat-2.5
Input1,048,576 tokens
Output131,072 tokens
ByteDance
Seed 1.8
Input256,000 tokens
Output256,000 tokens
Mon Nov 02 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both LongCat-2.5 and Seed 1.8 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

LongCat-2.5

Text
Images
Audio
Video

Seed 1.8

Text
Images
Audio
Video

Release Timeline

When each model was launched

LongCat-2.5 was released on 2026-11-01, while Seed 1.8 was released on 2026-02-17.

LongCat-2.5 is 9 months newer than Seed 1.8.

LongCat-2.5

Nov 1, 2026

0 days ago

8mo newer
Seed 1.8

Feb 17, 2026

8 months ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

LongCat-2.5 is available from Meituan. Seed 1.8 is available from DeepInfra.

LongCat-2.5

meituan logo
Meituan
Input Price:Input: $0.30/1MOutput Price:Output: $1.20/1M

Seed 1.8

deepinfra logo
Deepinfra
Input Price:Input: $0.25/1MOutput Price:Output: $2.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against LongCat-2.5 and Seed 1.8 side-by-side, then vote on the output you prefer.

LongCat-2.5
✓ Preferred
Seed 1.8
Open in Playground

FAQ

Common questions about LongCat-2.5 vs Seed 1.8.

Which is better, LongCat-2.5 or Seed 1.8?

LongCat-2.5 leads the LLM Stats Score 50.0 to 33.6. LongCat-2.5 is made by Meituan and Seed 1.8 is made by ByteDance. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does LongCat-2.5 compare to Seed 1.8 in benchmarks?

LongCat-2.5 scores MathVision: 96.5%, BrowseComp: 91.9%, CharXiv-R: 90.2%, Terminal-Bench 2.1: 88.4%, Video-MME: 85.2%. Seed 1.8 scores CountBench: 96.3%, AIME 2025: 94.3%, VLMsAreBlind: 93.0%, MMLU: 92.3%, AI2D: 89.1%.

Is LongCat-2.5 cheaper than Seed 1.8?

Seed 1.8 is 1.2x cheaper for input tokens. LongCat-2.5 costs $0.30/M input and $1.20/M output via meituan. Seed 1.8 costs $0.25/M input and $2.00/M output via deepinfra.

What are the context window sizes for LongCat-2.5 and Seed 1.8?

LongCat-2.5 supports 1.0M tokens and Seed 1.8 supports 256K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between LongCat-2.5 and Seed 1.8?

Key differences include LLM Stats Score (50.0 vs 33.6), context window (1.0M vs 256K), input pricing ($0.30 vs $0.25/M), licensing (Unknown vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes LongCat-2.5 and Seed 1.8?

LongCat-2.5 is developed by Meituan and Seed 1.8 is developed by ByteDance.

Related comparisons