Compare / head-to-head
LongCat Flash ChatvsSeed2.1 Pro
Seed2.1 Pro leads 1 of 1 shared benchmark.
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
0 – 1
Seed2.1 Pro leads
Cheaper per token
—
list price, input + output
Larger context
—
both 128K tokens
Provider uptime (30d)
— · —
Meituan LongCat · ByteDance Seed
LongCat Flash Chat
Meituan LongCat · released 2025-09-01
text
- Context
- 128K
- Max out
- —
- Input /1M
- —
- Output /1M
- —
- Cached /1M
- —
- Scores
- 31 · 9 core
Seed2.1 Pro
ByteDance Seed · released 2026-07-13
textvisionvideo
- Context
- —
- Max out
- —
- Input /1M
- —
- Output /1M
- —
- Cached /1M
- —
- Scores
- 26 · 2 core
Quality
Benchmark matrix
1 shared · 30 only LongCat Flash Chat · 25 only Seed2.1 Pro| Benchmark | LongCat Flash Chat | Seed2.1 Pro | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 1 | ||||
| BeyondAIME | 43% ↗ | 87% ↗ | -44 pt | Seed2.1 Pro |
| Only LongCat Flash Chat reports · 30 | ||||
| SWE-bench Verified | 60.4% ↗ | not reported | — | — |
| GPQA Diamond | 73.23% ↗ | not reported | — | — |
| MMLU | 89.71% ↗ | not reported | — | — |
| MMLU-Pro | 82.68% ↗ | not reported | — | — |
| AIME 2025 | 61.25% ↗ | not reported | — | — |
| LMArena Elo | 1422.9 ↗ | not reported | — | — |
| AceBench | 76.1% ↗ | not reported | — | — |
| AIME 2024 | 70.42% ↗ | not reported | — | — |
| ArenaHard-V2 | 86.5% ↗ | not reported | — | — |
| C-Eval | 90.44% ↗ | not reported | — | — |
| CMMLU | 84.34% ↗ | not reported | — | — |
| COLLIE | 57.1% ↗ | not reported | — | — |
| DROP | 79.06% ↗ | not reported | — | — |
| GraphWalks-128k | 51.05% ↗ | not reported | — | — |
| HumanEval+ | 88.41% ↗ | not reported | — | — |
| IFEval | 89.65% ↗ | not reported | — | — |
| LiveCodeBench | 48.02% ↗ | not reported | — | — |
| MATH500 | 96.4% ↗ | not reported | — | — |
| MBPP+ | 79.63% ↗ | not reported | — | — |
| Meeseeks-zh | 43.03% ↗ | not reported | — | — |
| Safety: Criminal | 91.24% ↗ | not reported | — | — |
| Safety: Harmful | 83.98% ↗ | not reported | — | — |
| Safety: Misinformation | 81.72% ↗ | not reported | — | — |
| Safety: Privacy | 93.98% ↗ | not reported | — | — |
| Tau2-Bench (airline) | 58% ↗ | not reported | — | — |
| Tau2-Bench (retail) | 71.27% ↗ | not reported | — | — |
| Tau2-Bench (telecom) | 73.68% ↗ | not reported | — | — |
| TerminalBench | 39.51% ↗ | not reported | — | — |
| VitaBench | 24.3% ↗ | not reported | — | — |
| ZebraLogic | 89.3% ↗ | not reported | — | — |
| Only Seed2.1 Pro reports · 25 | ||||
| Agent Startup Bench | not reported | 68.8% ↗ | — | — |
| BabyVision | not reported | 73.7% ↗ | — | — |
| CharXiv-RQ | not reported | 85.4% ↗ | — | — |
| CharXiv-RQ (with tools) | not reported | 86.4% ↗ | — | — |
| ERQA | not reported | 72% ↗ | — | — |
| KINA | not reported | 48.3% ↗ | — | — |
| MathVision | not reported | 92.6% ↗ | — | — |
| MathVision (with tools) | not reported | 94.5% ↗ | — | — |
| Minerva Video Reasoning | not reported | 70.7% ↗ | — | — |
| MMLongBench 128K | not reported | 78.3% ↗ | — | — |
| MMMU-Pro | not reported | 81.6% ↗ | — | — |
| MMMU-Pro (with tools) | not reported | 82.7% ↗ | — | — |
| NL2Repo-Bench | not reported | 47% ↗ | — | — |
| OVOBench | not reported | 80.7% ↗ | — | — |
| SuperGPQA | not reported | 70.8% ↗ | — | — |
| SWE-Atlas | not reported | 35.2% ↗ | — | — |
| Terminal-Bench 2.1 | not reported | 71% ↗ | — | — |
| TOMATO | not reported | 79.5% ↗ | — | — |
| VideoMME | not reported | 89.2% ↗ | — | — |
| VideoSimpleQA | not reported | 76.4% ↗ | — | — |
| Workspace Bench | not reported | 53% ↗ | — | — |
| WorldVQA | not reported | 53% ↗ | — | — |
| xDailyBench | not reported | 61% ↗ | — | — |
| ZEROBench | not reported | 18% ↗ | — | — |
| ZEROBench (with tools) | not reported | 22% ↗ | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is LongCat Flash Chat minus Seed2.1 Pro in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | LongCat Flash Chat | Seed2.1 Pro | Edge |
|---|---|---|---|
| Context window | 128K tokens | — | — |
| Max output | — | — | — |
| Input price / 1M | — | — | — |
| Output price / 1M | — | — | — |
| Cached input / 1M | — | — | — |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | — | — | — |
| Modalities | text | text · vision · video | Seed2.1 Pro |
| Released | 2025-09-01 | 2026-07-13 | — |
| Cited benchmark scores | 31 | 26 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
LongCat Flash Chat vs …
Models sharing the most benchmarksMore matchups
Seed2.1 Pro vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
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