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Claude Haiku 5.5 vs Seed 2.1 Turbo

Claude Haiku 5.5 leads the LLM Stats Score 50.0 to 42.7.

Anthropic · ByteDance · Updated for 2026

Which is better?

Claude Haiku 5.5 leads the overall LLM Stats Score 50.0 to 42.7, ranking #19 overall.

In the 3 individual benchmarks reported for both models, Claude Haiku 5.5 wins 2; this is a narrower head-to-head signal than the composite indexes.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Haiku 5.5

  • overall performance matters — it scores 50.0 and ranks #19 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 2 of 3 exact shared results
  • you want the most recent training data — it shipped Oct 2026

Choose Seed 2.1 Turbo

  • you are already invested in the ByteDance ecosystem

At a glance

The differences that matter most.

Claude Haiku 5.5
Anthropic
Seed 2.1 Turbo
ByteDance
Core performance indexes
LLM Stats Score
50.0
#19
42.7
#55
Reasoning
47.2
#27
44.1
#42
Coding
40.2
#13
29.8
#58
Agents
33.3
#28
28.2
#52
Cost, coverage & limits
Benchmark wins
2 of 3
1 of 3
Input price
$0.10 / M
— / M
Output price
$0.50 / M
— / M
Context window
1,000,000
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
Claude Haiku 5.5
Seed 2.1 Turbo
Math
25.7#110
39.4#18
Vision
30.4#33
30.2#34
Tool use
20.3#59
19.1#66
Multimodal
31.4#27
33.1#20
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

36 reported for Claude Haiku 5.5 · 90 for Seed 2.1 Turbo

3 shared

Claude Haiku 5.5 outperforms in 2 benchmarks (Program Bench, SWE-Bench Pro), while Seed 2.1 Turbo is better at 1 benchmark (OfficeQA Pro).

Claude Haiku 5.5 shows notably better performance in the majority of benchmarks.

Thu Oct 08 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Claude Haiku 5.5 specifies input context (1,000,000 tokens). Only Claude Haiku 5.5 specifies output context (128,000 tokens).

Anthropic
Claude Haiku 5.5
Input1,000,000 tokens
Output128,000 tokens
ByteDance
Seed 2.1 Turbo
Input- tokens
Output- tokens
Thu Oct 08 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Haiku 5.5 and Seed 2.1 Turbo support multimodal inputs.

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

Claude Haiku 5.5

Text
Images
Audio
Video

Seed 2.1 Turbo

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Haiku 5.5

Proprietary

Closed source

Seed 2.1 Turbo

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Haiku 5.5 was released on 2026-10-07, while Seed 2.1 Turbo was released on 2026-06-24.

Claude Haiku 5.5 is 4 months newer than Seed 2.1 Turbo.

Claude Haiku 5.5

Oct 7, 2026

1 days ago

3mo newer
Seed 2.1 Turbo

Jun 24, 2026

3 months ago

Knowledge Cutoff

When training data ends

Claude Haiku 5.5 has a documented knowledge cutoff of 2026-06-01, while Seed 2.1 Turbo's cutoff date is not specified.

We can confirm Claude Haiku 5.5's training data extends to 2026-06-01, but cannot make a direct comparison without Seed 2.1 Turbo's cutoff date.

Claude Haiku 5.5

Jun 2026

Seed 2.1 Turbo

—

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Haiku 5.5 and Seed 2.1 Turbo side-by-side, then vote on the output you prefer.

Claude Haiku 5.5
✓ Preferred
Seed 2.1 Turbo
Open in Playground

FAQ

Common questions about Claude Haiku 5.5 vs Seed 2.1 Turbo.

Which is better, Claude Haiku 5.5 or Seed 2.1 Turbo?

Claude Haiku 5.5 leads the LLM Stats Score 50.0 to 42.7. Claude Haiku 5.5 is made by Anthropic and Seed 2.1 Turbo is made by ByteDance. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Haiku 5.5 compare to Seed 2.1 Turbo in benchmarks?

Claude Haiku 5.5 scores Global-MMLU: 87.8%, MILU: 87.6%, BenchCAD (with Python tool): 87.0%, Chartography: 86.2%, SWE-bench Multilingual: 83.7%. Seed 2.1 Turbo scores CharXiv-D: 94.6%, MathVision: 92.7%, MathVista: 90.5%, MathVerse: 89.2%, Video-MME: 89.0%.

What are the context window sizes for Claude Haiku 5.5 and Seed 2.1 Turbo?

Claude Haiku 5.5 supports 1.0M tokens and Seed 2.1 Turbo supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Haiku 5.5 and Seed 2.1 Turbo?

Key differences include LLM Stats Score (50.0 vs 42.7). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Haiku 5.5 and Seed 2.1 Turbo?

Claude Haiku 5.5 is developed by Anthropic and Seed 2.1 Turbo is developed by ByteDance.

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