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Claude Haiku 5.5 vs Step-3.5-Flash

Claude Haiku 5.5 leads the LLM Stats Score 50.0 to 37.1. Step-3.5-Flash is 1.1x cheaper per token.

Anthropic · StepFun · Updated for 2026

Which is better?

Claude Haiku 5.5 leads the overall LLM Stats Score 50.0 to 37.1, ranking #19 overall.

On price, Step-3.5-Flash is roughly 1.1x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Haiku 5.5 also accepts a larger context window (1,000,000 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 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 process long inputs — it offers a 1,000,000 token context window
  • you want the most recent training data — it shipped Oct 2026

Choose Step-3.5-Flash

  • cost matters — it's about 1.1x cheaper per token
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Haiku 5.5
Anthropic
Step-3.5-Flash
StepFun
Core performance indexes
LLM Stats Score
50.0
#19
37.1
#82
Reasoning
47.2
#27
37.1
#81
Coding
40.2
#13
20.2
#109
Agents
33.3
#28
15.2
#99
Cost, coverage & limits
Benchmark wins
—
—
Input price
$0.10 / M
$0.10 / M
Output price
$0.50 / M
$0.40 / M
Context window
1,000,000
65,536

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Claude Haiku 5.5
Step-3.5-Flash
Math
25.7#110
33.9#52
Tool use
20.3#59
13.3#108
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

36 reported for Claude Haiku 5.5 · 7 for Step-3.5-Flash

No common benchmarks found

Claude Haiku 5.5 and Step-3.5-Flashdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Step-3.5-Flash costs less

For input processing, Claude Haiku 5.5 ($0.10/1M tokens) costs the same as Step-3.5-Flash ($0.10/1M tokens).

For output processing, Claude Haiku 5.5 ($0.50/1M tokens) is 1.3x more expensive than Step-3.5-Flash ($0.40/1M tokens).

In conclusion, Claude Haiku 5.5 is more expensive than Step-3.5-Flash.*

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

Lowest available price from all providers
Fri Oct 09 2026 • llm-stats.com
Anthropic
Claude Haiku 5.5
Input tokens$0.10
Output tokens$0.50
Best providerAnthropic
StepFun
Step-3.5-Flash
Input tokens$0.10
Output tokens$0.40
Best providerStepFun
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

Claude Haiku 5.5 accepts 1,000,000 input tokens compared to Step-3.5-Flash's 65,536 tokens. Claude Haiku 5.5 can generate longer responses up to 128,000 tokens, while Step-3.5-Flash is limited to 8,192 tokens.

Anthropic
Claude Haiku 5.5
Input1,000,000 tokens
Output128,000 tokens
StepFun
Step-3.5-Flash
Input65,536 tokens
Output8,192 tokens
Fri Oct 09 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Haiku 5.5 supports multimodal inputs, whereas Step-3.5-Flash does not.

Claude Haiku 5.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Haiku 5.5

Text
Images
Audio
Video

Step-3.5-Flash

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Haiku 5.5 is licensed under a proprietary license, while Step-3.5-Flash uses Apache 2.0.

License differences may affect how you can use these models in commercial or open-source projects.

Claude Haiku 5.5

Proprietary

Closed source

Step-3.5-Flash

Apache 2.0

Open weights

Release Timeline

When each model was launched

Claude Haiku 5.5 was released on 2026-10-07, while Step-3.5-Flash was released on 2026-02-02.

Claude Haiku 5.5 is 8 months newer than Step-3.5-Flash.

Claude Haiku 5.5

Oct 7, 2026

2 days ago

8mo newer
Step-3.5-Flash

Feb 2, 2026

8 months ago

Knowledge Cutoff

When training data ends

Claude Haiku 5.5 has a documented knowledge cutoff of 2026-06-01, while Step-3.5-Flash'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 Step-3.5-Flash's cutoff date.

Claude Haiku 5.5

Jun 2026

Step-3.5-Flash

—

Provider Availability

Claude Haiku 5.5 is available from Anthropic. Step-3.5-Flash is available from StepFun.

Claude Haiku 5.5

anthropic logo
Anthropic
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M

Step-3.5-Flash

stepfun logo
StepFun
Input Price:Input: $0.10/1MOutput Price:Output: $0.40/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Haiku 5.5 and Step-3.5-Flash side-by-side, then vote on the output you prefer.

Claude Haiku 5.5
✓ Preferred
Step-3.5-Flash
Open in Playground

FAQ

Common questions about Claude Haiku 5.5 vs Step-3.5-Flash.

Which is better, Claude Haiku 5.5 or Step-3.5-Flash?

Claude Haiku 5.5 leads the LLM Stats Score 50.0 to 37.1. Claude Haiku 5.5 is made by Anthropic and Step-3.5-Flash is made by StepFun. 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 Step-3.5-Flash 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%. Step-3.5-Flash scores AIME 2025: 97.3%, Tau-bench: 88.2%, LiveCodeBench v6: 86.4%, IMO-AnswerBench: 85.4%, SWE-Bench Verified: 74.4%.

Is Claude Haiku 5.5 cheaper than Step-3.5-Flash?

Both models cost $0.10 per million input tokens.

What are the context window sizes for Claude Haiku 5.5 and Step-3.5-Flash?

Claude Haiku 5.5 supports 1.0M tokens and Step-3.5-Flash supports 66K 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 Step-3.5-Flash?

Key differences include LLM Stats Score (50.0 vs 37.1), context window (1.0M vs 66K), multimodal support (yes vs no), licensing (Proprietary vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Haiku 5.5 and Step-3.5-Flash?

Claude Haiku 5.5 is developed by Anthropic and Step-3.5-Flash is developed by StepFun.

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